Adding bank accounts to Bisq app

New here.
Why do I have to add my bank account to the app. I thought the p2p service meant I would accept an offer of Buy BTC and pay the seller anyway I want.

This is important for me since I live in Pakistan and cannot use my bank account. I will have to use other payment methods to pay the seller into his bank account.

Do you have a list of payment methods acceptable to Bisq and most of the community, particularly for those from outside the USA.