Using D6000 as a switch wireless

[Ax0]

Hi there,
can somebody help me? I bought a wireless router D6000 to extend my home network, from one apartment to another, in the same floor.
The main router, gived to me by my provider, manages the network (wired and wireless) in my parent's aparment. I brought a wire from their apartment to mine and I've plugged the D6000 but the Netgear router create a new network, with a different IP range, automatically. All's work fine, in the end, but the Smart TV and others device (connected wireless) with a "simple" DLNA client dont read my NAS (from one network to another). Currently I've configured a Raspberry, in the 2nd apartment, as a DLNA server (getting file from the "main" network) but it's a bad workaround, for me, the Rasp is old and slow and using the Smart in that way is not user friendly for my girlfriend.
For long story short: Is there a way to configure the D6000 to get the same range IP of main fiber router, creating even a second wireless network (otherwise I could buy a simple switch)?
I'm not sure my english is comprensible, I attach a simple scheme

[antinode]

> [...] I bought a wireless router D6000 to extend my home network, from
> one apartment to another, in the same floor.

   Firmware version?  (The DSL-modem features of the D6000 would seem to
be useless for you.)

> Is there a way to configure the D6000 to get the same range IP of main
> fiber router, creating even a second wireless network (otherwise I could
> buy a simple switch)?

   You seem to want a wireless access point.  On a D7000
(V1.0.1.54_1.0.1), there's a one-step option:
       ADVANCED > Advanced Setup > Wireless Access Point

   As I read the D6000 User Manual, the D6000 does not have this option.
However, you should be able to make it work using the method suggested
in the following thread (for a C6300, but the principles are the same:

      https://community.netgear.com/t5/x/x/m-p/1463500

   I would start by configuring the D6000 with different wireless SSIDs,
so that you'll know which access point you're talking to.  But, if that
works, then you should be able to configure the D6000 with the same
SSIDs as your main router.  (If you want.)

> I'm not sure my english is comprensible, [...]

   It seems to be (easily) good enough.

   I can't see your picture yet, but you could visit
http://netgear.com/support , put in "R7000" for the model number, and
look for Documentation.  Get the User Manual.  Look for "Use the Router
as a Wireless Access Point".  See if the picture there looks like what
you want.  (The R7000 also has the one-step option, but its User Manual
has a nice picture.  With the D6000, you would use one of its LAN ports,
not its WAN/Internet port, as on the D7000 or R7000, however.)