Follow the other comment or, open the 'App Info' of default YT app (by holding dorn on the app icon). Goto 'open by default'. In 'Open supported links' choose 'Dont allow app to open links'.
For Revanced follow above and set it to 'Allow app topen supported links'. The supported links should already be availablefior revanced.
Or you can set 'Ask everytime' for both and chose when opening an URL.
That's Vanced. ReVanced is a new thing where you take the official YouTube APK(or some other apps)and patch it yourself. They have an app that does the hard work for you. You just have to find an APK for the right version of YouTube via APK Mirror or similar.