I'm a little confused as to what your paperwork actually says, because on the one hand you state
we have all the paper work that shows him as buyer
but then you go on to ask
how can I get my father listed as buyer instead of me?
It sounds like perhaps you have been listed as the primary on the financing agreement and you father is listed as secondary or maybe not listed at all. However, this is only one piece of the puzzle. The names on the financing agreement only specify who is responsible for repaying the debt, and as you are aware, each person named is equally responsible for 100% of that debt.
The other thing to check is the title or memorandum certificate. This will have at least one of you named as the owner of the vehicle, and then the financing company will be listed as a lienholder. With a lienholder present, you cannot usually sell or transfer the title of ownership until the debt to the lienholder has been settled. If you're both listed on the title, then you both own the vehicle. If only one of your named is on the title, then that is the person who owns the vehicle. This declaration of ownership trumps whatever is written on the loan paperwork.
Now, in terms of what to do next, you may not have to do anything. After all, you have already said
I would do anything for him
So even if your name is on the title and his isn't, you can still just let him use "your" car and make all the payments on the loan (this is a fairly common scenario with the roles reversed - parents buying cars for their children to use). Once the loan is paid off, you're free to transfer the title to your father by gifting him the vehicle (or selling it for $1 if that's more beneficial from a tax perspective).
You should double check that the insurance policy does not forbid a non-owner being the full-time user of the insured vehicle. In the two states I've owned cars in, this has never been a problem, but I can't speak for all 50.
Lastly I wanted to address the comment:
my father says if they can’t get it fixed, to where is name is listed
as buyer, then they can give him his trade in back and give him back
what he put in, and they can have the car back.
Unless you are in a very consumer-protective state or there was a clear case of deception, it's unlikely that this will really be an option. There is most probably a thick stack of papers with your signature(s) all over them that state something along the lines of "I understand what I'm getting myself into here and I agree to it", and when you ask the dealer to unwind the sale they'll just shake their heads and point at that stack. But honestly, your situation isn't that bad - if you have a good relationship with your father, just chalk it up as a clerical error and fix it in a few years when the loan is paid off.