Date: 202101
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Aircraft: Medium Transport; High Wing; 2 Turboprop Eng
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach
Airspace: Class B ZZZ
ATC / advisory: Tower ZZZ
Second aircraft: Any Unknown or Unlisted Aircraft Manufacturer
Reporter organization: Air Carrier
Reporter function: Pilot Flying; First Officer
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human factors: Confusion; Situational Awareness
Second reporter function: Pilot Not Flying; Captain
Anomaly: ATC Issue All Types; Conflict Airborne Conflict; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance
Detector: Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Executed Go Around / Missed Approach
Contributing factors: Environment - Non Weather Related; Procedure; Human Factors
Primary problem: Environment - Non Weather Related

Narrative: Coming to ZZZ on the ILS [Runway] XXR; we were continually slowed by ATC for spacing of traffic ahead and behind.  At about 1;200 MSL on glide path still IMC Tower told us to go-around.  I was PF and hit GA button and advanced power levers.  We went through missed approach procedure; but as flight guidance was attempting to be set the aircraft was also capturing the level off of 2;000 MSL so took a little longer to complete.  Meanwhile we were a little late on turning to 195 heading.  ATC queried us as we were in the turn.  We had also climbed to 2;180 feet before stopping and returning back to 2;000 immediately.  After we got settled ATC vectored us back to ILS with no further issues.  ATC told us they had to send us around because aircraft on final for parallel Runway XXL behind us had gotten .99 miles from us.  Spacing needed to stay a min of 1 mile.I should have paid more attention to altitude and started turn to 195 even if flight guidance wasn't quite set yet.  Also pulled back power sooner or not add as much to avoid going through altitude.


Second narrative: During our arrival into ZZZ; when told to run base (heading approximately toward ZZZZZ [Intersection]); we were slowed to 170 KIAS.  We were maintaining 4;000 feet throughout base turn and intercept turn onto final.  Once established on final (approximately 20 NM from ZZZZZ1 [Intersection]) we were slowed further to 160 KIAS; with traffic approximately 4 NM in front of us.  Once we intercepted the glideslope; we maintained approximately 1;000 feet above the preceding traffic; but gained to within 3 NM distance.  Meanwhile; ATC vectored a airline flight onto final for [Runway] XXL close behind us.I told the First Officer (PF) to potentially fly a half-dot high on the glide slope to avoid any potential wake from the preceding aircraft.  Once we reached approximately 10 NM from ZZZZZ1 [Intersection] we were slowed further to 150 KIAS.As we continued down the approach; the TCAS showed us to be approximately 2.5 NM from the preceding traffic; with the traffic behind us close in trail (unable to tell the specific distance).  At approximately 600 AGL; ZZZ Tower issued a Go-Around; with nonstandard missed approach instructions (Right turn heading 195; climb and maintain 2;000).  The First Officer initiated the Go-Around and the Captain (PM) proceeded to re-program the Flight Guidance.Due to the light passenger load; the subsequent climb rate caused the Flight Guidance to immediately switch from a Climb indication to an Altitude Capturing indication; which caught the Captain off-guard; and he tried to re-configure the Flight Guidance back to a Climb indication.  The Flight Guidance again sequenced to an Altitude Capture indication.  At this point; the Captain (PM) noticed the aircraft was off course to the left approximately 35 degrees and was rapidly approaching 2;000 feet.  The Captain brought this to the attention of the First Officer while also simultaneously acknowledging ATC stating 'Turn right heading 195.'  The Captain also prompted the First Officer to reduce the power setting; as the airspeed was approaching maximum flap speeds.  The missed approach up to leveling off at 2;000 feet was all hand-flown (i.e. not with the autopilot).Once the aircraft was established on the appropriate heading; altitude; and configuration; ZZZ Approach vectored the flight around for a second attempt at the ILS 16R; which occurred without further incident.  In researching the First Officer's seniority; he has been here less than X years (Date).  After debriefing the flight; he stated that that was his first Missed Approach / Go-Around in the actual aircraft EVER.Since we had been slowed down significantly early during the approach; we knew we could expect to be sandwiched in between other aircraft.  However; we did not know that ATC needed only 1 mile separation between aircraft on parallel ILS approaches (told to us by ATC during our second attempt).  There was no mention of spacing requirements on our first approach.Due to 'COVID loads;' the aircraft type climb rates are very good; requiring steeper than normal attitudes so as to not exceed flap speeds.  This factor; combined with the First Officer's relative inexperience with missed approaches; caused a momentary loss of situational awareness by the First Officer.This required the CA to not only re-configure the flight guidance for a missed approach; but also ensure the First Officer did not over speed the flaps; communicate with ATC; and ensure the aircraft was following appropriate flight guidance (which was a non-standard missed approach).Also contributing to the loss in situational awareness was the altitude at which ATC issued the Go-Around:  600 AGL.  This caused a significant startle factor in both the Captain and First Officer.  Had ATC mentioned anything about a potential missed approach; we would have been much more prepared.Last-minute ATC-issued Go Around instructions (below 1;000 AFE); caused by inadequate spacing with simultaneous parallel approach aircraft.RECOMMENDATIONS:1.  ATC NEEDS to let crews know 'be ready for a missed approach' if there is potential for a spacing issue.  We were given our Go-Around instructions at 600 AGL.  This is a very high-risk area to issue a Go-Around; when spacing throughout the entire approach was tight.  Some sort of notification to us would have primed for a potential Missed Approach and therefore could have avoided any loss of situational awareness and subsequent heading / altitude deviation.2.  STOP ISSUING NON-STANDARD MISSED APPROACH INSTRUCTIONS.  The ILS [Runway] XXR's Standard Missed Approach instructions are to fly runway heading to 900 feet; then climb on heading 195 to intercept the ZZZ 210 degree radial; maintain 2;000 feet.  This is VERY similar to what we were assigned (heading 195; climb to 2;000 feet).  However; when we're given nonstandard missed approach instructions; not only do we have to interpret what it is ATC actually told us; but also program that into the Flight Guidance.  This programming is CONTRADICTORY to what our normal Flight Guidance programming procedures are.  Had ATC simply said 'fly the published missed approach;' that could've aided in our appropriate handling of the aircraft.LESSONS LEARNED:Don't trust ZZZ ATC to not screw up.  If spacing looks tight; brief a missed approach; even if it's done on the Final Approach Course.  Also; do not trust your fellow crew member to fly a perfect Missed Approach.  Watch them like a hawk for course; airspeed; and altitude management; and IMMEDIATELY speak up if there is even a minor deviation.


Synopsis: Air carrier flight crew reported executing a go-around due to ATC spacing with another aircraft on final. The flight crew overshot their altitude during the go-around and cited the aircraft light weight as a contributing factor.