couldn't get IP address

> I bought anew hp printer. [...]

   Thanks for that detailed description of the printer, and how you wish
to connect it to anything.

> [...] HP Support couldn't get the printer to work because the router
> password would'nt work. [...]

   Which "the router password"?  Which "the router"?  Look for "Model"
on the product label.

> [...] how do I get my router password or change it, so the computer
> can work.

   "computer" or "printer"?

   Did you consider trying this radical concept (which works for some
people):

      https://en.wikipedia.org/wiki/RTFM

   Visit http://netgear.com/support , put in your (actual) model number,
and look for Documentation.  Get the User Manual (at least).  Read.
Look for topics like "Types of Logins" and "Basic Wireless Settings".
Further reading might not hurt, either.

   I hear that that sort of thing works at hp.com , too.

   General advice: "couldn't" is not a useful problem description.  It
does not say what you did. It does not say what happened when you did
it.  As usual, showing actual actions (commands) with their actual
results (error messages, LED indicators, ...) can be more helpful than
vague descriptions or interpretations.