if you can join the army, that's the one to go for, at least you will learn real life skills that you may find easier to intergrate into the american way of life with (shooting and hunting and stuff like that) than the motorsport degree where you will be fairly limited in the fields of work you could put down on a visa application

plus, the army still deduct money from you for rent and food and stuff but you don't get to spend any of the stuff you earn really so it's fine, my cousins just bought a house with cash money he's saved up and he's only been in the army for about 7 years