We have answered this question above in great detail. To briefly summarize it, you will have to first see whether you fit into one of the categories that are eligible for receiving a free car from dealerships.
Please see the section above to check. After that, you will have to fulfil the procedural formalities. You will have to choose the best dealer option in your city that has a running program for giving away donated cars to low-income people and other individuals. In the end, you will have to justify the requirement of a free car for earning or for any other reason.