Tips on confidence/jealousy

Sooo I feel like this will be a weird question... lol but I was wondering if I could steal any tips on being more confident/less jealous.

The problem with myself is I have no problem thinking that I look good, have a good personality, and i think of areas of myself to improve on, rather than shitting on myself for things I don't like.

YET, I get jealous and territorial all the time towards my boyfriend and friends. I don't feel like I have trust issues because my boyfriend and friends have never done me wrong, and I've never suspected them of doing so. But maybe on a subconscious level i do have issues? Just because of past situations in other relationships, that could be a possibility.

So I guess I'd really like to tell myself to get over myself 😂 but have no idea of how to do so.

And please, no negative comments, I'm literally asking how to improve myself lol.

Also, i wasn't 100% sure where to post this, so sorry if I picked the wrong category 😬