How do i bring up that i want to have psychiatric evaluation/start therapy to my parents?

Hi, i live in the us and am 17, turning 18 next month and am wondering how to go about telling them i need help.

For context ive suffered from sh for years and various eating disorders, and other issues that have affected relationships and hurt others and my self from and i want to get help. Im just unsure what to say or how to do it and I'm a bit scared.

Any help appreciated thank you so so so much!