Writing your own story around the same ideas is not plagiarism; at worst, it's being unoriginal.

I do not click on random youtube videos.

The one thing that does happen, every time, though, is that I never get to write a book until I've already been thinking about it for a period of months to years.

When I do get to chow down on a book, I try to read ones that are nothing like what I'm writing. So, as I'm currently working on a space opera (of sorts) I'm mostly indulging in urban fantasy.

I grew up on second hand bookshops and libraries.

While writing a novel I almost completely stop reading books in the same sub-genre for the duration.

Writers block: when I get it, it's because my subconscious spotted that I'd make a huge structural mistake in constructing a novel before my conscious mind became aware of it, and threw on the brakes. So I've learned not to sweat it: take two days off, then back up a chapter, read through, and try to work out why I'm suddenly uneasy about continuing.