Decided yet Confused. Please Help.

I got offer from University of Leeds business school in MA Advertising and Marketing while my background is bachelors in design. I think now I want to learn the theoretical side of design management but few of my friends from abroad keep telling me that going from design to business school is such a bad idea and that I should wait another year or I'll be left with no career of future in this field. Someone please guide and help me get out of this confusion since my thsi course session starts from September, 2023. P.s I am not really good at designing but very creative in ideas pitching and stuff. please suggest. I plan to be an art or creative director someday so don't know if this field is right for that either.