1996 Ford Thunderbird

My mom recently got a Ford Thunderbird and accidentally drove it into high water and flooded the engine and they gave it to me so I can drive it to school when I get my license but I have to fix the knocking in it I'm not a mechanic (I fix phones. Difference) so I don't know what I'm doing. What should I do to fix the knocking and it does start just the knocking. I think haven't really messed with it yet

You have a PROFESSIONAL inspect the engine. It may not be POSSIBLE to fix without replacing the engine. It may not be WORTH fixing in any case.