Another thing that someone told me which is equally important is that if they like you they will find time to go out with you and spend time with you, if they repeatedly say they are busy then they aren't interested, no matter how much you feel otherwise, it's not going to happen.
That being said, you can't rely solely on them liking you and it requires effort to be romantic and do things which will convey romance.
I was talking to a girl for months who I knew liked me but I literally just held her at arms length when I could've been flirty and when I finally realized I liked her I had spent too long not reciprocating and she had lost interest. Obviously you think she is interested so go for it and see what happens, I was scared of rejection by this girl that I didn't talk to her romantically for months but once I did, she responded in a way which showed that she did like me but I was just confusing myself.
One word of warning, do not text just this girl or speak to solely her because it will honestly frazzle your head, because you think of them all the time, 5 minute replies infuriate you and every song reminds you of them, keep it healthy and text 2-3 people or atleast keep yourself occupied and busy because you can get proper depressed overthinking your every interaction with them,