Used to be my coworker. I flirted with her back then but she is very shy and had a boyfriend back then. Met her couple of days ago accidentally, we talked and decided to meet up for a lunch. Its not a date, just wanna talk to her to understand if i wanna move my game on with her... Any advice? How should i act on that lunch in case i am into her?

I will have to set up a date after for sure that i know, but any other advice would be nice too.