Withdrawal System for Earning App

Good day family of developers.

I am Gideon and total beginner in android development using java language and android studio.

I am currently working on my final project which is “an online earning system”. This app allow users to perform certain task, answer quiz, watch ads, answer questions and earn certain amount of coins per transfer.

The area I had issue with is how to enable users to be able to withdraw their earnings to their respective bank account once the withdrawable amount is reached.

Thanks all