You can write your topic however you want, but you need to answer these questions:
What do you want to achieve? Keep it simple and clear!
So I am a builder and don’t know much about scripting (gives me headaches), but for a game I’m working on, I want to add “Boats” into it, But… I want it to drive using the “Endorsed Car Models” Chassis. Here’s the link to the endorsed cars: Sedan - Roblox
What is the issue? Include screenshots / videos if possible!
The best way I can see you doing something like this would be to make a part underwater, then attach a boat to the top of the wheels, which could create the effect you want. Though I’m not sure that using a car chassis is the best solution in the first place, you could using body movers to move the boat around instead.