How many versions of LR do I have on my computer, where are all the files scatered? How do I undersatnd what is the most current LR and files needed to run it? How do I know what. to trash? It's a mess, what tool or resoruce is there to focus the choas of Adobe products? Thank you.
"How many versions of LR do I have on my computer"
Go to the Adobe Creative Cloud app and see what is installed. Here's what mine looks like, I have Lightroom Classic installed (it says I can open it) and I do not have Lightroom installed (it does not say I can open it).
I have LR & LRC, do I need both?
I also have 3 Photoshops
"I have LR & LRC, do I need both?"
That's pretty much up to you. Lightroom stores your photos in the cloud while Lightroom Classic stores your photos on your local computer (amont other differences)
"I also have 3 Photoshops"
How do you know? If you open them, which is the most recent version?
Do I need all of these?...
Most people don't need earlier versions of Photoshop, unless you need them because of bugs or some other reason to compare older versions to new versions.