Nighthawk AC1900 R7000

albeit disappointed Netgear owner can't email query (crappy customer service),  grateful there is a support thread of knowledgeable users...3 simple questions:

1.  How many devices (cells/tablets/FireStick) can be used within home before needing to upgrade??

2.  I initially loaded several devices at once, rather than one at a time (idiot) so do NOT know what several of the devices listed in my "Network Family" are....

     How do I determine which address/icon belongs to individual devices (so I can 'name'/label each one)??

3.  Seems more often than not, whenever I open my Netgear icon, the thin banner above the icon tiles announces "new firmware" or "new Netgear update"

     is available...even though I just downloaded (with all appearances successfully) said update the prior day/week/etc??   Or are there numerous updates?

Appreciate any/all advice/assistance/guidance...please converse in "near-idiot 60 year old just recently crawling into 21st centur-speak"