[Redmi Note 9 ROMs, Kernels, Recoveries, & Other De] MyBrainIsAStrainer:
Hmm... all I see is a neverending blue and white arrow symbol.

With the OpenGapps test builds for Android 11, or the NikGapps, the installer always complained about not enough space on the system partition, even though it was already the smallest package (pico/core).

Only the FlameGapps basic package installed without errors on my device, but since it doesn't boot, I can't tell you if it actually works.

Here's the log from the OpenGapps pico package:

# Begin Open GApps Install Log
------------------------------------------------------------------
ROM Android version | 11
ROM Build ID | RQ1A.210205.004
ROM Version increment | eng.ebincr.20210225.160609
ROM SDK version | 30
ROM/Recovery modversion | v11.0
Device Recovery | TWRP 3.4.2b-1213-c4a6db32
Device Name | merlin
Device Model | M2003J15SC
Device Type | phone
Device CPU | arm64-v8a,armeabi-v7a,armeabi
Device A/B-partitions | false
Installer Platform | arm
ROM Platform | arm64
Display Density Used | 440
Install Type | Clean[Data Wiped]
Google Camera already installed | Clean
VRMode Compatible | false
Google Camera Compatible | true
New Camera API Compatible | false
Google Pixel Features | false
Current GApps Version | No GApps Installed
Google Camera version | Legacy
Installing GApps Zipfile | /external_sd/Download/open_gapps-arm64-11.0-pico-20210130-TEST.zip
Installing GApps Version | 20210130
Installing GApps Type | pico
Config Type |
Using gapps-config | Not Used
Remove Stock/AOSP Browser | false[NO_Chrome]
Remove Stock/AOSP Camera | false[NO_CameraGoogle]
Remove Stock/AOSP Dialer | false[NO_DialerGoogle]
Remove Stock/AOSP Email | false[NO_Gmail]
Remove Stock/AOSP Gallery | false[NO_Photos]
Remove Stock/AOSP Launcher | false[NO_GoogleNow/PixelLauncher]
Remove Stock/AOSP MMS App | false[NO_Messenger]
Remove Stock/AOSP Pico TTS | false[default]
Ignore Google Contacts | false
Ignore Google Dialer | true[NoRemove]
Ignore Google Keyboard | false
Ignore Google Package Installer | false
Ignore Google NFC Tag | true[NoRemove]
Ignore Google WebView | false
Total System Size (KB) | 1186384
Used System Space (KB) | 971236
Current Free Space (KB) | 198764
Additional Space Required (KB) | 25676 << See Calculations Below
------------------------------------------------------------------
# End Open GApps Install Log

INSTALLATION FAILURE: Your device does not have sufficient space available in
the system partition to install this GApps package as currently configured.
You will need to switch to a smaller GApps package or use gapps-config to
reduce the installed size.

NOTE: The Stock/AOSP NFC Tag is not available on your
ROM (anymore), the Google equivalent will not be removed.
NOTE: The Stock/AOSP Dialer is not available on your
ROM (anymore), the Google equivalent will not be removed.
# Begin GApps Size Calculations
------------------------------------------------------------------
TYPE | DESCRIPTION | SIZE | TOTAL
| Current Free Space | 198764 | 198764
Remove | Existing GApps | + 0 | 198764
Remove | Obsolete Files | + 56 | 198820
Remove | extservicesstock | + 0 | 198820
Remove | extsharedstock | + 52 | 198872
Remove | packageinstallerstock | + 3284 | 202156
Remove | provision | + 0 | 202156
Install | Core | - 174976 | 27180
Install | calsync | - 2556 | 24624
Install | dialerframework | - 32 | 24592
Install | googletts | - 37896 | -13304
Install | packageinstallergoogle | - 3156 | -16460
| Buffer Space | - 9216 | -25676
------------------------------------------------------------------
Additional Space Required | 25676
------------------------------------------------------------------

# End GApps Size Calculations

# Begin User's gapps-config

# End User's gapps-config