Questions: Flirting

A bit more context that might change your answer/opinion:

So I already learned some of the letters from the native language of this girl I like and showed her. Later today, I google'd opinions of people from across the web and they say it can be creepy and impractical if you're only learning it to impress her.

Of course, I intend to learn more languages anyways, so why not start with one I've never heard of?

Anyways however, her reaction was more of a giggle in the beginning and a "you did good" afterwards. If this is a good sign, it throws me off because sometimes she shows signs like she doesn't care (not saying "bye" for example at the end of the day and just walking home with her friend, or NEVER initiating conversation with me but occasionally waits for me to walk with her while her friend is by herself). If you have anything to say about this, let me know in the opinions.

Im thinking in aproach a girl that works on a shop and try to make a pick up line with her and the name of the shop... and i know she will laugh but can i have a date with that? or is better a normal aproach?

we met online dating and my bio was "no one can beat me at FIFA :P". when we matched she said "I can beat you at FIFA :p"
then we talked about other random stuff off that topic. she took a long time to reply tho (like hours at times) so I brought up the FIFA joke again and said "its gonna be fun beating you at FIFA :P" I kinda sent that late (around 1am) and then next morning she replied "lol We'll see about that" . now I don't know what to reply.

what that a subtle way of stopping the convo because she lost interest or is she still interested and I make a move like ask her out?

please give opinions and answers too on what I should do!