Login with biometrics

Hello everyone,

I have a few questions I’d like to ask you all. I’m a game developer who mainly works with Unity and I have zero experience with native Android development.

Right now I’m trying to implement a biometric authentication feature whose purpose is to securely retrieve a stored token (then use that token to log the user in). From my research so far, I think I need to implement these two things:

1. Show a biometric authentication dialog (fingerprint/face/iris)
2. Use the Android Keystore system

But I’m completely confused about the actual encryption/decryption flow itself.
Besides the Keystore and the Biometrics library that I already know I need, what else do I still have to add or implement for the encrypt/decrypt part?

In short, besides the two things I already listed, what else am I missing to make this work properly and securely on Android (from Unity)?

Thank you so much in advance!