First you need to check the terms of your loan (or call them) to see if they do accept early settlement. Some awkward s0ds do not, or make it so difficult so as to be effectively impossible.
The loan agreement may give some idea of the costs of an early settlement, but for an exact amount you'll have to call them for a figure.
Yes, you often get heavily penalised so they can make up the lost interest. The penalty varies with the loan company. Some are perfectly reasonable, others are very mercenary.
Then compare with the new loan you intend to get, and see if you save any money.
Yes, with a personal, unsecured loan and the original agreement paid off, the car would be yours to sell.