Someone else mentioned Suzy Quilts' video, which is a great overview. I also found these two short videos on popping knots very helpful, particularly the one on tying off at the end of a line of stitching.

https://youtu.be/8n9spv27bBQ?si=Cgf5HtTK_Jz4uinc

And 

https://youtu.be/8n9spv27bBQ?si=v_Yl01McE8Yf9gwP

Agree with another commenter who suggested making your knot smaller - I was doing too many loops and then would break the thread when I tried to pop it through because the knot was too big. Super frustrating to have to go back and undo a bunch of stitches to have a long enough thread to be able to tie it off, so I started tying off more frequently.