@zale_orcid Have a look at this:
intersect_cylinder.gh (30.2 KB)
Your questions individually are pretty simple, but when you put them all together and create the starting cylinders the definition starts getting large.
I recommend using either Sunglasses or Bifocals to display component names (especially while learning). I prefer Sunglasses because it seems slightly less obtrusive but both are very helpful.
You will get more help here if you try to make your own files and upload them with specific questions about where you’re stuck.
Learning grasshopper seems a bit overwhelming at first but it gets easier once you’re past the initial learning curve. Read the references, follow tutorials, and experiment by putting together your own definitions. Most questions have been answered somewhere in these forums. You can learn a lot by examining the files others have posted while answering questions.
-Kevin