The boy asked the girl to see a movie for the first time, hugged her when he broke up, and sent a message to the girl saying that he was very happy. What does this mean? What should I do next?

It shows that he is very interested in you and enjoys his time with you. The message indirectly indicates that he hopes to see you again next time. If you have a good impression on him, you can send messages to each other, such as "I had a good time, too, and I will come out together next time." It's nothing. Let's talk about it and see how it feels.