How to make a vertical split screen video?

[ShiroKuro]

I would like to try adding the score to my video the next time I make a piano video. I want to set it up so that the video showing my hands is at the bottom and the score is at the top, and the score moves along as the music moves along. I always film my hands using a tripod over my shoulder, so the hand-video will be horizontal, then I could add the score, one or two grand staves at a time, across the top.

I would also like to do this in the simplest way possible

I can use powerpoint, put the scores onto the slides and click through the slides so that the score follows the music. I could also just use the “snipping” tool on PC (I think) to make a video of the score moving, and presumably save that as an mp4…

So does anyone have any advice about what the easiest way to combine the moving score (video of score) with the video of me playing? I have access to Kaltura and also Canva, but I’ve never used either. I have a PC, so maybe there’s some free MS app I could use? I used to use Camtasia, but no longer have access to the paid version and don’t want the watermark that it adds to the free version.

I do have an iPad, so maybe iMovie could work? But I’ve never used it for something like this before.

Thank you in advance for any advice!