What is the ruling on a bank deposit with a fixed monthly return and a loan taken from it to purchase a car, both from the perspective of the deposit and the loan?

If the loan is interest-based (riba) and the interest is fixed and predetermined, then it is forbidden, and one must repent from it by disposing of the interest through spending it on general Muslim welfare. The money should be withdrawn from the interest-based bank if possible. The money can be deposited and invested in an Islamic bank or in a current account that does not accrue usurious interest.