Picking up on hints is a thing that requires a lot of social context and emotional empathy/intelligence. Unfortunately I don't think there's any pro tips I can offer to help you better identify them except interact with girls more and have honest conversations where you're not trying to get the girl to date you - it's learning the hard way, but bridging that emotional understanding gap is the only good way to get a better understanding of girls as people (and get your heart rate down so talking to them isn't a panic).

That said, if you can find the confidence, being a little blunt yourself can work as well. Girls can be dense too.

A lot of the reason girls are doing the subtle hint stuff is because they're also not confident / unsure / scared of rejection / scared of coming off too strong. It's a way of feeling out a situation without strong commitment. We kind of expect guys to do that back so that we can have a sort of subtle social fencing game to figure out if there might be mutual interest. (unfortunately, most of the time, everyone involved is too dense for this to be effective)

Honestly both sides kinda suck at this in their own ways.