We get a lot of requests to switch the method for which one can log into their Tinkercad account. For example switching from the "Sign in with Facebook" method to "Sign in with email" method.
In short, we cannot change the way you will sign into your account as you set it up initially.
If you need to switch the method you will sign into Tinkercad, then you may create a new account using that method.
Note that signing in with a different social sign on option will create a new account even if it is with the same email you used for another Tinkercad account.