What makes somebody a friend, and what makes them a potential love interest?

Hello and good day to whoemever may be reading this, Title is a question that's been sitting on my mind for a while now.

This post isn't meant to be relationship advice, even if it might seem as such, more so I am genuinely confused and don't really catch on with it anymore.

I've been trying to get into a relationship for a while now, I've also had women I was personally interested in, but in the end it would always end with us as good friends and nothing romantic coming out of it.

I personally don't see a problem with "being friendzoned", it is not like I feel detached from a person or feel insulted just because it didn't work out.

It has been happening so often however that I am starting to question on whether I am just missing out to take specific steps to have my relationships with people move into that direction?

That is why I wanted to ask if any of you could tell me at what point if you are in a relationship or were in one, have you felt romantic feelings develop towards a person? Was it linked to a specific behaviour? A specific moment? Circumstances?

I am really just wondering if its just that I haven't found the right person for me yet or whether I am just missing out on steps along the way?

I will keep on trying to find the right person for me regardless, but in the case that I am actually just forgetting something I would hate if a possible relationship would also never come to happen just because of my ignorance about most things romantical-

Thanks for any answers or help along the way.