Be aware then most lessons are given in an older version of Blender.
And the new Blender 3.x.x has a major overhaul in code and render engine (Cycles-X).
Using an older version is the best way to cope with new problems.
You can install multiple versions of Blender!
Blender installs itself in a different folder.
As a beginner, you don’t miss much with version 3.x.x.
- You are using Eevee, which is using default setup in a very simplistic way. To gain render speed. So many things are different in comparison to Cycles. You need to switch a lot of options in Eevee to improve renders. But then Eevee will be slower.
- Eevee renders volumetrics as a cube
- Change the density of the volumetrics, to 0.1 ranges and see what is happening.
Let us kown, how you are making progress.