Cannot connect using ethernet conection

> [...] a wifi router (N750 wireless dual band) [...]

   "N750" is a speed, not a model number.  Ever helpful, Netgear product
packaging emphasizes speeds like "Nxxx", but that's not the model
identifier.  Look at the label.

> [...] all Netgear products.

   Swell.  How are all these things connected?

> With the exception of the new products, nothing else has changed,
> network wise.

   I'd say that a new modem and a new router would be enough changes to
make some difference.

> [...] now I am unable to Lan wire my 2 Samsung Tvs, my home security
> system and my PS4!

   "I am unable" 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, ...)
can be more helpful than vague descriptions or interpretations.

> I have done all the troubleshooting techniques and still nothing.

   That non-description conveys no useful information about what you did
or what happened when you did it.  Do the LED indicators on these
devices indicate anything?  If you connect a computer directly to the
CM700, can you communicate with its management web site?  And if you do
the same thing with the (unspecified) router?

   In general, you might start with getting the modem connected to your
(unspecified) ISP.  When that works, add the router, and deal with that.
When that works, start adding other devices.

   If you don't already have the User Manuals for these devices, then
visit http://netgear.com/support , put in each model number, and look
for Documentation.  Get the User Manual(s).  Read.