How to edit in different clips together (stacked)

[XeonNetwork]

So I watched a video :sparkles:  :sparkles: - YouTube which it had multiple clips of the mouse manipulating the picture with the other mice.
Can anyone please explain how to do this?

[Peru Bob]

That was likely done using screen capture software and an application like Photoshop and may be more than one screen recording mixed in Premiere Pro.

[XeonNetwork]

Yes but I'm saying how did he combine the clips in premiere pro like do the transparency and such.