In course 4, I reached video number 7 on week 2.
The content is confusing for me and I am unsure if I should restart course 4 or if there is a better way to proceed
Perhaps review the video lectures a few times.
Yeh, figuring out the Conv/pooling layer and their resulting dimensions is hard. I found it helpful to draw the layers on paper following the lecture. Good luck!
Back to the previous videos, watch and carefully take notes. Then you get a better feeling. After that you feel more confident to move forward.