MIT or UMD full ride? Chemical Engineering intended major

Unfortunately, your parents’ confusing signal is not a good sign. Sometimes, parents give a signal like what you are getting when they really do not have the money, but cannot bear to say “that is too expensive” because they do not want to give you a huge let-down now. But they could be setting you up for an even bigger let-down after a year or two or three of college if they run out of money (and/or borrowing capacity if they take parent loans for your first year) so that you will not be able to continue through graduation.