I find an incredibly beautiful girl, she's at my job what to do ?

In most cases if a girl is into you'll know about it. Even shy people talk with their eyes and body language. So if you haven't sensed any attraction from her it's probably safe to say it doesn't exist. 

Maybe if you talk to her? Hopefully, you actually speak better than you write.

make conversation with her for starters,get to know her,smile and compliment her,find out what u likes, u snooze u lose....never fear rejection..
you'll need to draw on your courage. Start by being subtle and dropping hints...  Looking someone in the eye is akin to trying to get their attention. 

ask her whats her favorite movie..In order to get to know every aspect of your crush, you actually have to talk about yourself a little. See how they respond when you do, whether you're just making conversation or revealing personal truths. See if they listen and ask questions the way you do when they're talking.

It doesn't really matter whether or not she is interested in you; what matters is whether you are interested in her and what you are gong to do about it.

"Faint heart never won fair lady"! If she thinks you might be frightened of her she will not respect you.