You cannot borrow enough student loans without a cosigner to pay for the full price of either. Your father is being unrealistic.
With respect to the schools, are you directly admitted to your major at UT? If so, then you do not have to worry about the competitive admission process to get into your major at Purdue, but changing to another engineering major at UT may be more difficult. Of course, that may not be a concern if you earn a 4.0 every semester, but very few students do that.