"Continue with phone/google" alternate methods?

You see log in/sign up options like this:





Are there alternative ways to work around this. Google is pretty hard with how one can manage emails iirc. I can't make unlimited emails under the same phone number and idk how many Google accounts can come under the same device. Have to resort to buying aged accounts.

With phone numbers idk about any other methods. I can only use a phone number per account so that doesn't help with multi accounts.

There's a FB option which is simply just aged accounts as my solution but I'm not focusing on that. More on the phone and Google side.

Anyone?