I can't find the Google drive application on screen

Hello.

Swipe down from the middle of the Home screen to access the Spotlight Search. Type in "Google Drive" or whatever it's called and it should show up in the search results with the name of the folder it's in next to it.

The one thing I could think of is that you have a ton of apps installed, right?

iOS has a limit to 9 Home pages. You can still install apps on your iPhone, but they won’t be visible until you delete some from the Home pages or organize them into folders.

Then keep looking through all of the pages of the Home screen until you find it. It's there somewhere.

Have you located the folder the app is in?