Car repairs

Hello, I am asking for help fixing my family’s car. My father was in an accident that totaled his truck (our only vehicle). We searched for awhile and decided on a car from a lot. Turns out it had lots of problems that we were not told about prior to buying it. It will overheat and shut down completely quite often, making it a safety hazard. We have already bought a new battery and brakes for this car. We believe the transmission is going out. Sometimes the car refuses to start causing us to miss work. We are living paycheck to paycheck and cannot afford to take it in to get repairs. We would be very grateful for any help you can provide us. Thank you.