Courses and free learning materials like blog posts have transformed education. Free contents are available in such quantity that you are literally drowned. In this era, it’s about choosing the best materials.
The first thing is to see if the content has been suitably broken down. Something teaching the Dijkstra algorithm is expected to let users have notions of weighted graphs, directed graphs, spanning trees, connected graphs, BFS, DFS, stacks, queues and min heap. Then the algorithm is a piece of cake. Else only a definition then moving to the code is troublesome.
The second thing is to look at the exercise or assignments. Often the material teaches you about mining ores then the first question is about polishing diamonds. If the gap between the level of the exercises and the learning material is too wide, people won’t benefit. Actually exercises serve 4 purposes which we’ll cover later on. It’s best to have a range of questions either separate or as a single continuation.
In short, learning materials should teach you enough for you to master a subject. If you find you don’t understand programming it’s for you to bridge the gap. That’s why the path is more important than contents.