I would think you would be doing the same “pre-med” as any other person hoping to go to med school. Bio/Chem etc. yes, you should take highest maths. Math is math. We have AB and C calculus here, so I doubt it is “much harder”.
Many internationals hope to come to the U.S. For school and then stay and work here. Very few are permitted to do so. I would not plan on staying.