Welcome to PF!
Please take some time to read our site's global guidelines (link below in my signature). We have a few topics that we don't discuss, like perpetual motion machines.
We try to stay within the bounds of mainstream science. This includes topics in your textbook or published papers in research journals. It doesn't include someone's website or YouTube video channel unless they are well-known as a science presenter like Veritaseum (Science, Math, Engineering...), or Smarter Everyday (Engineering), or 3brown1blue (Math concepts) or Khan Academy.
When in doubt, you can ask a mentor via the report button if it's okay to post your source video or article in response to some thread here. We may not respond immediately, but we strive to respond within a day or so.
We do entertain questions about concepts, problems, and paradoxes in mainstream science, but we don't discuss personal theories or personal research.
Take care,
Jedi