Is there anyway I can call Handheld.PlayFullScreenMovie(), and have interactable elements on top of the video? like a button or something. Also, is there anyway to play videos not fullscreen on android?
Any other approach for android that I can have a video playing and other interactable elements at the same time?
No you cannot without using your own plugin. And even that might not be possible or so easy.
When launching the movie, Unity is paused, so no code is run from Unity. The app hands over the control to a secondary app with some parameters. At the end of the movie or when you tap, the movie app closes and gives control back to Unity.
So all in all, no you cannot.
The solution is to use plugins for movie like LiveTexture from Prime 31. This one is not free but dunno if there is any for free.