Going from "Anti-Virus" to "Security"?

Hello,

I've been having somewhat of an issue or question that I couldn't find answered elsewhere. We currently have Norton-Antivirus running in our home for five computers (purchased back when it was still available). Now that Norton Anti-Virus doesn't really exist anymore, we want to buy Norton Security as a separate product, rather than extending the license.

I'm curious to know if I can purchase it, then leave it unactivated until I need it (which is in like 30 days) and then essentially reinstall Norton, or better yet, immediately activate it and update to Norton Security. I'm a bit confused about the two products. While looking the same, the name of it says "Anti-Virus" for me, whereas with Security  it actually would say "Security".

Are they two separate products?

Can I use the license I receive from buying Norton Security Premium on my current Norton Anti-Virus and just not worry about it?

Can I, or do I need to store Norton Security on my account until Norton Anti-Virus expires?

Will other PCs that are registered under a different account (also Norton Anti-Virus) work with the serial license upgrade/update automatically, or at all? (Our neighbor chips in with us if possible and vice versa. I maintain his computer, which is why I ask).

 

If anyone can enlighten me about the wall of text (sorry), I'd appreciate it, and it'll probably give me the certainty to purchase Norton Security, as it's a little less expensive and also much better than extending the current Norton Anti-Virus license.