AC1750 Smart Wifi router not broadcasting a signal, says its offline

> - On the forums on the site, [...]

   Thanks for the helpful links.

> [...] I cannot get the modem connected to the internet so I cannot
> check my version of the firmware of the Wifi router.

   You don't need an Internet connection to talk to your own router.

> [...] Get the User Manual (at least). Read. [...]

   Did you?

> - Ethernet, what else would that mean. [...]

   "LAN" and "wired" are spelled differently for a reason.

   "LAN" = "Local-Area Network".  That would include both your wired and
wireless connections.  The LAN Ethernet ports on your router are labeled
"LAN".  There are no places to hang labels on wireless connections, so
they are not labeled "LAN" in the same way, but they're still part of
your LAN.

> - It is apparent it is not the modem, there's seems to be issue with
> comcast modems and Netgear wifi routers

   It may be apparent to you.  With my weak psychic powers, it's not
apparent to me, hence the question.  I'd expect it to be easier to
answer the question than to argue about how irrelevant the answer might
be.  My time is apparently more valuable to me than it is to you.  I'd
prefer to waste less of it this way.

> - I have tried following steps that one of the forums here listed to
> the letter and I am at a loss.

   Again, with my weak psychic powers, that tells me exactly nothing
about what you did or what happened when you did it.

   Did I miss something, or do we still not know what the LED indicators
on the R6400v2 indicate?  Plenty of other unanswered questions, too.
Look for "?".

> [...] (just says its a Gateway cable modem)

   It has no maker or model number?  Really?