BMW X5 vs Honda Civic as a first car?

I'm getting my first car soon and I'm 17 going to college next year, Honda Civic would be the better option I'm guessing if I'm paying for my gas and insurance myself, but the bmw is sort of fuel efficient w just a 7 mpg difference and nicer, would I be delusional to assume that I could keep up with the expenses of a bmw without any help from my parents? (not paying for the car myself)

I think it is a good option

7 mpg is a huge difference. And in real driving the gap will probably be even bigger. Not to mention the repair costs for an X5 are catastrophic compared to an X5. Plus I don't even think the X5 is a particularly good vehicle. If you want a BMW, why not get a 5 or 3 series?