Lots of talk about torque wrenches and calibration, but for the OP, whatever brand you choose, consider spending a little more for a torque angle wrench. These days cars are full of torque-to-yield fasteners, where you tighten the bolt to a specific value and then turn it another specified number of degrees. It’s not just head gaskets anymore. Simple brake pad and rotor replacement, CV axles, etc. can use TTY fasteners. There are methods to calculate 90* or 60* of turn, but when it’s built into the wrench it’s a whole lot easier.
Throw it in the back of your car, and next time you’re driving around and see a Snap On truck at an auto shop, step in and ask if you can check the calibration of your wrench.
They are elegantly simple but not really practical for use anymore. I mean maybe for a DIY’er, but in a professional setting can you imagine a guy using a beam wrench for lug nuts? How much time would that take?