I have Win11 DeskTop Computer and Movie Studio 15 and I know how to take a video with a green background and overlay it ontop of another video.

Then I remove the green color and it looks like the video is ontop of the other video.

I do not know if anybody can help me with what I want to do now?

I have a video of a zombie girl moving with a green background.

I want to be able to open my Door and have her standing there.

Now if I put the zombie girl video ontop of the video of me opening the door I can croma key the green background in her video so it looks like she is standing here.

The thing is as I am opening the Door I want it to show her like she is stand there behind the Door.

I do not want to open the Door then have her video just pop her in.

I hope I am asking in the right way?

Thanks for the time.