How do you upload videos for download

Help
#1

I was scrolling of the forums when I see a screen recording.
I clicked it and I downloaded it
This would be a good way to upload my wick to my channel from my school computer (that cant email people out of of my organization) to my PC and send it to YouTube. It doesn’t take mp4 videos tho

What do I do?

#2

Maybe a video hosting website and then embed it on here

I got this example from w3schools

Random notes (CLICK THIS)

w3schools is not a video hosting website (well that’s what I think),
w3schools is for coding examples and tutorials and I also sometimes use it and I also recommend it.