How can i let go of anxiety, and be myself?

I'm a freshman in high school, and for years I've had this problem with overthinking, and analyzing situations, also I'm a perfectionist, to the point where I get really bad anxiety when I make a mistake. My parents tell me they want me to try to be perfect, and they push really hard, but this anxiety is getting in the way of my daily life. (also I may be getting checked for ADHD) Whenever I make conversation with people, I get nervous, and I always feel the need to be funny and bubbly all the time, and thats not totally me either. What are some things I can do to relax, and feel comfortable being myself?