Thank you so much! I've never knitted anything before (yet!) so I'm not sure if you can apply it. For crochet there's regular tapestry and another neater version of it.
Here's a video I found about it https://www.youtube.com/watch?v=6RLrJZNLWPA
I think this explains it way better than I could and you can actually see if you can apply it for knitting!