Try telling your dad, "You know I’m going to grow up to be me, don’t you? You can’t expect me to grow up and be another you."
It sounds to me like your dad needs reminding that kids need guidance, but they also need ‘space’ to form their own opinions and discover their own strengths and weaknesses. Tell him that instead of nagging you, it would be really helpful if he’d be willing to answer your questions, and let you talk so you can get your head around things that you’d like to discuss.
You can give me more clues (like your age) and carry on the conversation with me in the Comments section at the bottom of this article, if you like.