Welcome oldbibo! Very best etc
If there’s anything you don’t understand then do just ask; I do - a lot. I’m fact I’m a pain for constantly asking questions. (I’m full of pain drugs all the time, so I get confused.

)
Kitz and her team have written a lot of excellent pages in the site explaining how things work so just nose around. Beware some pages are over ten years old, and exceptionally valuable in giving a detailed snapshot of how things were back then, so ‘updating’ them would destroy valuable material. Just be aware that for today’s picture, you will need to look at the much more modern alternative informational material that is also available here too.