I used Sequence to control the camera, the Billbord, and the platform under the person's feet, and created an animation of a person flying. However, to ensure the smooth operation of the system, I don't want to run it using Unreal in the end. Instead, I hope to record the background as a video, and overlay the video played as the background with the Billbord, so as to make the person appear in a three-dimensional scene environment. But currently, I don't know how to obtain the signal after the Billbord is processed, and I also hope that it can be captured by the camera animation.