How should I start talking to this girl I like?

So I’ve been going to the mall a lot lately. I’m going there to try to get over this sort of social fear I have and to start talking to people more easily. So I was with two friends and there was a lot of people. this was yesterday btw. I came to the mall nervous and stuff but anyway, we walked into a store and the most beautiful girl jumped out towards us and was like “Hey what’s up!!” It kinda freaked me out a bit at first haha. so she works there. and so we walked down an isle and a belt fell. I picked it up and hung it back up and the next thing I know, this girl is right next to me saying stuff like thank you so much that was really nice, and most people just walk by and knock things down without caring. So to me at least I thought that she kinda liked me. cause she came across the store just to make random conversation with me and she looked at me a couple times. but anyway! I wanted to talk to this girl sooo bad. and I was just like in chock or something and I just couldn’t do it. like if there was a freakin invisable wall in front of me keeping me from going up to her. I felt ashamed.. but I’ve always been really shy like this. And I was thinking, well since I’ve been going to the mall lately, maybe I could like go next week on the day I seen her and try to talk to her. but I need help.. it’s just really hard and I want to soo bad. and I realize I have nothing to lose. and if she ends up thinking im weird, so what there’s other girls right? but there’s just something about her that I’m really attracted to.. besides being pretty haha. what do you think I should do? what should I say? how should I come up to her? how could I get her to like text me or somethin iono. or ask her out or somethin. there’s just something that’s.. intimidating, probably cause I’m so attracted to this girl hahaha and it makes this so much harder than it really is. and I feel kinda weird for liking someone that works at the mall hah. is that normal? btw im 16. she looked like shes probably 17. just any advice would help please. thanxx :)