How to transfer or migrate apps to new phone?
The answer will depend on which phone(s) are involved. Can you let us know?
if the apps come from the Google play store you should have an option to restore apps from another phone that was linked to the google account on first power up to set up the apps in the android setup screen (on new devices and after a Factory Data Reset)
if the apps cam from somewhere else (like amazon or another apps store) then you need to go back where you got them (or where you backed up the APK of the app)