Where do I set up the plugins and themes in my network?

I am assembling my criteria and questions to bring to you for some answers and clarification, but for now, I think I should go ahead and install the plugins I expect to be using in my multisite network. Let me know if I should install particular things first, and where. My main question as I begin is where do I install the plugins and themes?

I assume that I should install them to the network admin for use throughout the network.

I believe I understand it this way. All tools used in the network come from the central install, that is network activated.

Please advise or confirm.