The name of the app that comes with your Mac is "Photos" (not photo). What name are you hoping to use for that app?
(As jdb8167 wrote, renaming an Apple app is probably not possible, even if you have a good reason for the change...)
But, the idea mentioned about making an alias of that app, then changing the name of the alias will work, and you can then use that alias to launch the app when needed. However, the original app would remain in place, with the original name. You can't change the actual name of the app.
The app (and its name) are protected by the system.