Flirting with girls online/by text. I just can't do it 😩

So I don't have a problem getting numbers, some girls give it to me themselves, so I know I'm not ugly af or something.

I'm generally funny, my friends and female friends would describe me as one of the funniest guys they know. BUT when in texting an attractive girl, I DONT KNOW WHAT TO SAY (sorry for the caps lock, ahem anyway)

Like I'll be confused on what to say, and the convo will be boring, just talking about how's uni going or something like that. I can't seem to get any banter going, I overthink and then be too nice. By too nice I mean, I just ask nice polite questions and am too cautious to not offend them. How can I break the ice in this situation and get a good conversation going? I just never know what to say.

I can't even talk sexual, because I just feel like a dirty pervert if I do. Even though it's so common for people to talk sexually 😫