A friend of mine who is away wants to help me pay off my credit card debit. I don’t want to give my personal info out. He said that until I’m comfortable I can pay it using his account and routing number. Is that possible? How does it work ?
This is almost certainly a scam. You'll make some payment from the account, something will go wrong, you'll need to pay them back, then the payment from their account will bounce.
Since you've never met this person in person, their identity is probably false. They probably have been doing this to several people at once and have a lot of experience gaining confidence of others. Why can't they just make the payment themselves?