Guys & girls. Pls help me out.

I'm a guy who never talked to girls. I'm a very shy guy & always avoid talking generally. Due to this I never knew how to mingle with friends. Recently I met a girl through a training program. And I liked her. We conversed a bit. And both left for their hometown. Now I messaged her and chatted a bit. But I don't know how to continue or prolong the chat. I feel like the conversation is going one side. She's asking about me and stuff. But I don't know what to chat. I'm afraid that I might say something inappropriate. Please help me out. What kind of conversation can be done. And what are the things I can ask or I shouldn't ask. Please give me some advice. I already posted it in Chennai subreddit. So far no response. I hope you guys help me.