I think each school might be different. Some schools dont provide any financial aid to international students. Others will provide aid for any admitted student and if that is the case, then you do need to fill out the FAFSA (as best you can since some items don't match up) and then they will use it to assess your financial need. You will NOT get federal financial aid, BUT you may get school financial aid and the FAFSA forms are just the standard way of assessing you.