First, bookmark your subscriptions page on YouTube and always start there. Don’t look at the front page, don’t look at the side bar, turn off autoplay.
Second, on the Instagram app always start by touching the IG logo at the top left and choosing Following. This removes all suggestions (and even ads in my experience) from your feed. I think it puts it in chronological order, too.
The internet is full of fun, creative and interesting stuff! Take back some control so that’s the stuff you see.