Troubleshooting

Cannot resolve symbol 'AGP'

The project is using an incompatible version (AGP X.X.X) of the Android Gradle plugin. Latest supported version is AGP X.X.X

You need to update your android studio. this issue will fixed.

Cannot resolve symbol 'BuildConfig'

It's not a real error, it's just a false positive, it occurs when the project is opened for the first time or the project is not yet in Build, this problem will be automatically resolved after the project is built.

Cannot resolve symbol 'R'

This issues happens after you've Refactor > Rename your package folder with a new name, actually it's also not an error, we could say this is one of the bugs in Android Studio which until now have not been or are not fixed, as in the previous case, it's not a real error, it's just a false positive and will automatically resolved after you Invalidate Caches in your Android Studio project, you can do this by selecting File > Invalidate Caches... > Invalidate and Restart