Relationship advice

Ive been friends with this person for 4/5 years, and ive really been close to them for the last 2. He tells me everything, every little thing thats bothering him and I do the same. We're open with each other about everything, apart from where we stand relationship wise.

We attempted a relationship in the very early days and it didnt work out, but we've changed a lot in 4 years and part of me feels like it would be better this time around.

He invites me as his plus one to family events, theres a constant line of communication between the two of us via text or phonecalls (literally we talk every day, he usually initiates conversation) and we schedule to meet up just to hang out at least once a week, usually more. Im close to his family, he's close to mine. He's really shy and inexperienced relationship wise, as am i, which makes me feel like we maybe couldve fallen into a kind of routine with each other?

So my questions are:

Does this sound like the beginnings of a relationship?

Should i risk a good friendship and ask him out?

Is it ever ok to rekindle a relationship with your ex? Can people really change?

All i know is that, although i love every minute i spend with him, i always leave feeling disappointed that i have to let him go.

Thanks for taking the time out to read this! Sorry if its a bit long winded, im new to this posting lark

It sounds like you are really close friends, people can change as they get older but only if they decide to.