Bike parts are a bit awkward. Since they're made of soft materials, small bolts normally require quite a low torque figure, with bolts on seatposts and stems typically requiring around 5Nm and some proprietary parts going as low as 2Nm. Typical ranges for small bike parts go from 2Nm up to 20Nm.
That's not a range that many mass market torque wrenches cover, so don't expect to be able to use a torque wrench from an auto parts shop on your bike. Likewise, bike bolts are often small and have hex or Torx heads, so you need specialized bits to fit them, while access may be an issue. So you'll probably need a specialist bike torque wrench to adjust small parts on your bike.
On the other hand, if you're planning to work on larger components like bottom brackets, drivetrain and pedals, specified torque figures are usually a lot higher,  often around 40Nm. A torque wrench that can handle low torque for small bolts often does not have a range that extends that high, so you may find you either need a second, higher rated torque wrench or that you need to take your bike to a shop for these parts.