Hi there,
I guess I know what you mean. The whole PMBOK stuff is a little bit chicken & egg if you know what I mean

You must at first understand each and every knowledge area and process on the famous page 61 in the PMBOK in detail
and only than you are able to
start learning from scratch again and understand step by step how they are all linked.
In the second learning round you can create maps how all processes are linked to get your big picture or buy these products from RMC Project Management (Rita Mulcahy) which helped me a lot. (poster, flash card...)
If you have later specific questions about a process let us know and we will help you.
Cheers
Sven