Girls say you don't have to be careful when you talk to me?

First of all, this girl may think that you can't let go of talking to her, and the girl feels uncomfortable, so she will tell you not to be careful. This shows that this girl is extroverted.

Secondly, this sentence may be testing you and letting you go. After all, only by letting go can you see whether you are a trustworthy person or an untrustworthy person who talks big.

Girls are generally reserved, and I am embarrassed to say a lot. You can try to approach a girl and test her feelings for you. If they are fond of each other, you can get along further.

I hope my answer is helpful to you.