Connect 2 Wireless Router in one Network

[Cemozi]

Hello People;
At office we have 2 wireless Router modem (Asus Dsl-AC55u and Zxyel )VMG3312-B10B) they both have their own internet access (means we have two internet account).
On Asus is our server connected on zyxel are security cams.
What i want two achieve is When I'm connected on zyxel ( or My boss) want able to connect to server to check files without switching between Modems.
(Asus has 4 lan port but all are used )
Both modem have Wan ports but I dont want that modems internet acess stay split.
any idea how i can do it? is it possible?

 

[BFG-9000]

You'll need two NICs in a computer, so you could for example connect to ASUS wirelessly and ZyXel on ethernet simultaneously. Or two wireless NICs and connect to both networks on wifi at the same time. You will then be able to access files on both networks without having to switch anywires or SSIDs.

Under adapter options--advanced--advanced settings under "Connections" there are up and down arrows on the right side to change which NIC is your primary for internet. With two NICs installed, internet access will automatically fail-over to the secondary adapter if the primary network goes down.