What should I do if I need to collect player information via email?

I want to collect the player’s information via his email. (In this case I’m using Firebase login) What I need is When a player logs into my game with an email address they’ve played in before I want the game to load the player’s most recently played data to display, such as the level of the level they have played or their latest total score. What should I do? Please help me.
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2pi
What conditions do I need? If I want my game Load data from each player’s email. and the same What conditions do I need to use to save each player’s information to their email?
1pi