Yes, you have to acknowledge the authority and primacy of the pope in order to be Catholic. The pope is the earthly head of the Catholic Church, and to be in union with that Church you must be in union with its earthly head. By checking your user profile
, I found that you are Protestant. If you believe that the Catholic Church is the only true Church, or suspect that it might be, then I strongly urge you to study the issue of the papacy more closely so that you can understand what the Church teaches about the papacy. Surely, if the Catholic Church is the only true Church then it follows that one should study what that Church teaches and follow that teaching if it is found to be convincing.
Church and Papacy
Upon This Rock
by Stephen K. Ray
Papacy Evangelization Guide
by Stephen K. Ray and R. Dennis Walters