I am sure someone has asked this before.
But can you put in the course/videos the version of Blender you are using?
I think the video I am currently watching is on a 2.80ish I think, and I am on version 4.0.something, so we can nip back to the version you are using in the videos or look at the change notes when we lose or can not find the thing you are talking about.
Also, regarding the idea of spec you are using in the videos, in the geo nodes video, you talk about this action taking a few mS, or you see it slowly building the image. It takes almost no time when I am following, though, so you have an idea if you have forgotten or got something wrong, as it is taking a lot longer or is a lot quicker.
(The spec of your computer on the older video will not even run Version 4.)
Roger