Admin Account

> [...] So technically I dont think I'm posting these questions to the
> right group. [...]

      https://community.netgear.com/t5/x/bd-p/en-home-routers-nighthawk-wifi-ax6

> [...] I only want one admin account and I want to name it something
> else. Is this possible?

   Generally no, not on Netgear consumer-grade routers.  (There might be
some exceptions, but if it's not mentioned in the User Manual, I'd infer
that it's not possible.)

> 3) I use a ddns service and I find it very wiered that if I type in
> the ddns address [...]

   Do you "type in" some "address", or a [D]DNS _name_?  (Or does it
make no difference?)

> [...] I get prompted to log into my router. How do I disable this
> externally?

   Where, exactly, is the web browser where are you doing this?  Some
computer/device on your LAN?  Have you tried doing it _really_
"externally"?

> [...] I would like to log into my router when I'm at home (internally)
> but not expose this when I'm outside of my local network. [...]

   First, verify that the router actually does "expose this" to the
outside world.  It might be "helping" you more than you'd expect.

   Visit http://netgear.com/support , put in your model number, and look
for Documentation.  Get the User Manual (at least).  Read.  Look for
"remote access" and/or "Remote Management".

> [...] with a default admin user account of admin doesnt that
> potentially make it easir to hackinto?

   That'd depend on your choice of password.

   When it comes to ease of guessing, what's the practical difference
between:
      user = <other_name>   pass = <short_pass>
and:
      user = admin   pass = <other_name><short_pass>

?