Can we give a vehicle back if we cannot afford it to avoid bankruptcy? How?

In general, you would not have a general right to surrender the car and cancel the note unless the dealer agrees. So you might well try to win the dealer's agreement. A bankruptcy would rid you of the debt. It is possible that the dealer's delay in completing the registration shows some back story involving fraud. A dealer is expected to give good title to a car in return for your payments and agreement to pay more in the future. So one possible basis for cancelling the whole deal is that the dealer cannot give what you bargained for clear title to the car. (Clear but for any lien the dealer may have.) Discuss this with a Consumer Rights lawyer in your locality.

As a general rule, you can't renege on a contract. However, the buy-here pay-here place is running a scam on their lender. Car dealers usually borrow money to get their inventory, then whenever a car is sold, they pay off the lender for their loan on that car. This is called a "floor plan credit line" (because it pays for the cars in the dealer's showroom floor). The dealer hasn't informed the lender that the car has been sold which is why they can't give you a title. Park the car at the dealer's place and get away, then call them and tell them you brought it back because they didn't give you the title OVER THE PHONE, tell them you will report them to the state attorney general if they give you any problem. Then mail them the keys. Don't do this in person, you are dealing with sleazeballs, and they can get violent.

You can surrender the vehicle to the lender, but that won't relieve you of making payments. What will happen is the lender will sell the car at auction, and then charge you for the deficiency. The dealer MIGHT be willing to take the car back, but I wouldn't count on it. You'll have to check your paperwork to see what their policy is regarding returns. Bankruptcy is an option, but you should look at your entire situation to see if it's worthwhile. You can surrender the vehicle in a bankruptcy and not have to pay any deficiency.

I doubt it, but let a lawyer look at your papers.

That would be a yes.

In every car loan contract I have ever seen, other than contracts between friends, if you return the car, you are legally required to pay the difference between what the car sells for at wholesale and the balance owed on the contract. Most of the time, the car will sell for one third to one half of what you expect it ought to sell for. This balance is called a deficiency, and having a deficiency is a major reason people hire me to file bankruptcy because it almost always results in a large court judgment.

See an attorney, you MIGHT have a potential of rescinding the action as title has not passed.