Autorepair

I bought a used car at the end of 2019. The person who sold the car stated that it offers a one-year quality guarantee. I bought a semi-automatic Mazda car from 2007. My car suddenly did not put in a gear at the beginning of the month I was near my house. I found a repair shop to repair the car. The initial price was basically negotiated. Today I went to the repair shop and asked if my car did not repair who and I still need a certain amount of money to scrap the car? Should I switch to a repair shop? Before I switch to a car repair shop, I wonder if the next car repair shop can fix the problem. Do I have to pay for the current car repair shop? Can I find compensation for the sale of the car?