How do relationships start?

Hey reddit, I’m a 23 year old male who’s never been in a relationship. I’ve been through hook ups and girls that I really enjoyed being around but nothing ever comes from them. As much as I’d like to start one I never understood how. I know this sounds so dumb but I’m confused and need guidance on how one should form. I’m not the type of person to force a relationship and I thought they just form naturally but in my experience it’s been nothing but heart ache and disappointment and the girls ultimately finding someone else. Please help