How Can I Enable The Internal Option In The Oauth Consent Screen?

When I trying to choose the Internal option in the OAuth consent screen it tells me Because you're not a G Suite user, you can only make your app available to external (general au

Solution 1:

The only way to make an internal app is to create the project from a gsuite domain account.

Login to Google though your gsuite domain email and then go to Google developer console and create a project there. Then your project / application can be set to internal and used internally within the gsuite domain.

If you do not have a gsuite domain then you can not set your project internal and it is there for must remain external.

External apps will need to go though the google verification process.