Hey @jins I know this is very late, but I came here looking for answers to your number 2. I do have answers to your number 1 though - so I’ll drop that here in case others need it too.
Specifically, what I did, was use the LOCK tool which allows for customization of the login page: https://auth0.com/docs/libraries/lock. There should be a configuration object you can modify using the code editor of the universal login page where you can specify the text of a button. Documentation on those config options are here: https://auth0.com/docs/libraries/lock/lock-configuration