Hi Michaelsgirl and welcome.
We have a few people on the forum who have been 'friends', but where the relationship seems to be changing to 'something more'. Some people feel comfortable with this; others feel that it might put the original friendship in jeopardy.
Personally, I think that partners should also be best friends ~ but I can see a problem should the relationship not work out. Could such a friendship survive a failed romance??
Who knows? You are quite young, so relationships will be changing anyway.
If you know him well, then you could probably tell whether he might be interested in you in a romantic way.
I suppose you could always ask him if he would like to go somewhere with you ~ the cinema perhaps ~ as your date ~ and see what he says.
Welcome to the forum.