I live on social security disability and a small pension under two hundred from Dow chemical. I was sued and lost a claim about car repair. The mechanic did not preform all the work he stated,but I had no witnesses, He gave me the car and then demanded more money. I am paying but now the court in Ohio says they can garnish my benefits and take my car, What can I do?

You need to show that you need the car to get to appointments.
Also show that they are taking your social security. That is illegal as far as I have read.

Federal law makes Social Security benefits exempt from levy, garnishment, and assignment- 42 USC 407(a) states.
But you have to show they are taking social security.
Social security is only garnishable by some things such as student loan, or government (child support, taxes, etc.)
Others if they are allowed to garnish are only allowed a percentage. But again you need to show the bank, the court, social security, whoever that the money being garnished is social security,