I was chatting online and a girl said she wanted to marry me.

The girl's principle is like this

But you don't know each other very well

The girl is just sticking to her vow, she doesn't know you

You are the same, you don't know her, you can't be a couple just because of one word

You'd better meet each other first and be friends

If you really find it suitable, then you can have a relationship

It's better if you can meet each other first. If you really find that you are right for each other, then it's good to get into a relationship.

I hope I can help you.