How to get an Auto Loan

I was able to find a job after a year of being unemployed but I need a car to get there. I have always had problems of transportation and I cannot do uber or lyft. Where I live there is no public transit and I cannot bike to work. I need advice on how I can get an auto loan. I have good credit and I have an offer letter indicating what my pay would be but I do not have a down payment.

I was thinking of going through a credit union but I am also looking at where I currently bank (wells fargo and ally).

Can anyone give me some advice on this subject