Place a video file in the Assets folder of your Unity project.
Keep the pixel size small such as 426x240.
Keep the video duration short.
Use h.264 .mp4 (h.265 works)
These formats might work, depending on the codec: .mov .mpg .mpeg .mp4 .avi .asf
Select your object
Select Add Component in the Inspector
Choose Video->Video Player
Drag your video clip from the Assets tab onto Video Clip in the Video Player in the Inspector
If does not have have audio, turn off Audio Output Mode
If your video looks too dark create a new material shader
Select Shader->Unlit/Texture (In the Inspector)
Drag the Material onto your object
Pay the Game to see the texture
Directions to use Adobe After Effects
Directions to use Adobe Media Encoder to make a H.264 movie