Netgear C3700 Modem/Router

> I recently connected a c3700 router/modem to xfinity cable and cannot
> get to the correct site to change the sign in password to secure my
> wireless access.

   "cannot" 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 with their actual results (error messages, LED
indicators, ...) can be more helpful than vague descriptions or
interpretations.

   Visit http://netgear.com/support , put in your model number, and look
for Documentation.  Get the User Manual.  Read.  Then, if you still have
problems, return with a useful problem report.