User Profile

Hey, So me and my team are developing an app to be on the apple app store, now we wanted to first release the app on an invite-only option or to be invited by an existing user, I have read before that this is not possible because it will break a few guidelines, So my question before we decide to go that route, We wanted to know if it was possible and if it's not how did the new app Clubhouse did it with more than 90k downloads? https://apps.apple.com/us/app/id1503133294 can anyone explain how do we do it without breaking the guidelines?

Hey, I have a small question regarding the signup with Apple option on onbarding, So I have been working on UX/UI on App for the first time using this method and It seems to be that if we let users signup with apple, they do not need to create a password, now since they do not do that, they do not have a password on our app, and because of that they cannot sign-in in the future using our email option by itself, so my questions to those who have been experiencing it before, what is the best options in case scenario, To let users sign up with Apple and while onboarding to let the users add their on a password to our app so they can sign in with the email in the future? To let users sign up with Apple, and if they want to create a password to their account, they will go to their profile to create one or will press the "forgot password" when trying to recover their password? After signup using the Signup with Apple option to automatically generate a shuffled password and email it to the user so they will be able to always create a new password if they needed it. If they used the signup with Apple, let them always sign in with apple. Please any suggestions or options are welcomed Thank you!