Most of the major streets all have names and usually signs in English as well though.

And many cities are set up in grid systems. Fairly easy to navigate in most cases.

Google Maps works just fine most of the time.

Puzzling out the addresses can be challenging, but even that is a lot easier now with Google Translate.

And if all else fails, you can always ask someone. Usually Japanese people will go to extradionary lengths to help you out.