Create YouTube videos on exercises of a University level course Is it acceptable to create YouTube videos about exercises of a University level course ?

I struggle to follow a quantum mechanics course I need to take and thought about making YouTube videos where I explain the exercises and their solutions provided to us step by step. I already did that for two math courses last year, and not only did it help me a lot, it also helped other people that watched my videos. But some people told me to be cautious, because after all I did not create those exercises by myself and thus I have no right to talk about them in a YouTube video.

What should one do in those cases ?
As an alternative to basing your videos on someone else's work, I suggest writing your own exercises. Each exercise should bring out the issues you want to cover in the corresponding video.

If you write your own exercises, on your own time, you own the copyright, and can do what you want with them, including creating videos about solving them.

That would be superior from a learning point of view, because your users will be able to watch your video, learn from it, and then check their understanding by completing the coursework.