Crush on my friend

I have kind of a crush on my friend but she is interested in another girl and the only reason they aren’t dating is because the other girl is too young to date (we are all in high school). Anyways my friends and I agree that that girl is not good for her because she sends her threw so many emotions and my crush is super attached to her like the girl isn’t bad my friend just deserves better. I really wanna tell my friend that she should move on and that I like her but at the same time I feel bad and don’t want her to think that I am saying that because I have romantic interests in her. What should I do?