Every time I try to download Apps why I have to use Apple ID & password

Why do I keep seeing my Apple ID when I go to download an app and asked for a password every time why do I have to use my Apple ID password every time I wanna download something. OK when I first got my iPhone SE I could download Apps just using my fingerprint but now I'm seeingI that I gotta put it in my Apple ID password I don't understand why all of a sudden I change it back to my fingerprint after that I see that it wants Constant card information which I don't have any more cards I can load for payment I have how can I change this fixed

[Edited by Moderator]