Well, not exactly because Facebook and most internet social platforms are artificial. For example, it appears most of the womens' profiles on Ashley Madison were, uh, synthetic. But why? It's not going to be a real conversation. You'll probably not be able to further discuss what you find out. And also, it's a bit dishonest, wouldn't you agree? Instead, try to develop your powers of observation and deduction. From a Facebook profile alone, it's often possible to tell considerably more about someone than they think they have disclosed. As long as it's going to be anonymous speculation, you may have all the information you need already. Even better, just tell the person you like that you are gay, in a direct or some other reasonably effective way. Perhaps you'll have your answer.
I'm just afraid of Jeopardizing, like I'm afraid they will tell other people. And I'm already scared. One time maybe 3 years ago I was sitting with the girl I liked and she told me that she knew a girl on that team and that she was a lesbian and that she is freaking weird. What does that mean? I noticed that she wears a white shirt under every T-shirt she wears. Is that a sign?
I do get the social risks. That's where that developed power of observation comes in. Now, on that other thing, I' the last person in the universe who would be an expert, or even have a clue about any secret lesbian "hanky codes..." If this last phrase confuses you, take a look at this: https://en.wikipedia.org/wiki/Handkerchief_code I'll have to leave it to an experienced lesbian to answer that last question...
Faustian1 has already covered a lot of stuff and I would urge you to follow his advice. It's never a good idea to be fake, and when you get caught (which is highly likely) it will all backfire on you in a really horrible way. Sometimes we need to take a step back and consider the repercussions.
