Hop on a peertube instance. There are ones made by normal people, eg. https://urbanists.video (this one probably won’t accept your registration, but just showcasing).

If you heavily compress your videos or if they’re not very long, you could also upload a .mp4 file to a file host or just your own website (johndoe.com/myvid.mp4). Then the browser would just download and play the .mp4 file.

I want to buy a thinkpad that I can set up as a privacy machine

The older ThinkPads can go much further in the freedom/privacy realm than new ones. If you think you’d want to set up a custom BIOS etc., look at T440. There’s also T430 but it doesn’t support 4K output on external monitors. But you said you’re not “especially tech-literate”, so I assume you’re more towards the newer ones.

The video below makes the point “old but modifiable” vs “new and fast” https://www.youtube.com/watch?v=y2OB6zfL904

but muh headphone jack!!

but muh headphone jack

nice clickbait headline man