You get a bluetooth device that plugs into the odb port, or a patch cord that you connect to your raspberry pi. There are fancier ones with more features, that

You get a bluetooth device that plugs into the odb port, or a patch cord that you connect to your raspberry pi. There are fancier ones with more features, that can do more than just report signals like watch for certain signals or changes. https://www.amazon.com/s?k=obd+bluetooth+adapter https://www.amazon.com/s?k=obd+bluetooth+adapter