Convo starters

So ive been on some dating apps to talk to strangers and just chill with them. there ive met this dude and enjoyed talking to him. Once we moved to our personal socmed acc, it got boring. It also adds the fact that im not really talkative in chats, im just active in my circle of friends but other than that, i dont talk to others and because of that i dont know how to approach/chat him. We also dont have anything in common, we just enjoyed talking in that dating app, so idk how to start the convo. What to do?