Identify fuse that is off/bad but not tripped
To verify you have the correct one, turn off every other breaker one at a time and confirm that it controls whatever it says it does. By process of elimination, you can be fairly certain which breaker controls your garage because there should be one breaker that doesn't seem to control anything.

Thoroughly check your garage for a tripped GFCI outlet. It used to be common for an outlet in the garage to be a GFCI outlet that would protect all the bathroom and kitchen outlets, or all of the exterior outlets. The overhead lighting should not be protected by the GFCI, but I've seen stranger things.