Before I start dumping points into Charisma and the LL perk, I want to know one thing. Is there any way to intertwine or set up supply lines between several camps so that all your camps are sharing the same junk or are supply lines more linear?

Supply lines supply resources to all settlements in the "chain". e.g. if settlement A is connected to settlement B and settlement B is coonected to Settlement C then A is connected to C.

Just to be clear, the "sharing" is onlly for crafting and settlement food/water. You can't deposit some items in settlement A then pull it out in settlement B. However, you can use the junk in A to build/mod in settlement B.

Any settlement connected via trade routes to another is also connected to all other settlements on the network. Think of trade routes as roads. So long as you can draw a line between settlements with pre-existing trade routes, there is a way for your provisioners to get there.

As an example: if Sanctuary has trade routes to Red Rocket and Abernathy and I connect Sunshine Co-op to Sanctuary, it will then instantly get connected to Red Rocket and Abernathy as well.

Like how you used the transitive property to explain that haha. Thanks for the answer.