Remote connetion of Nighthawk AX3000 to T-Mobile gateway system

I have a Netgear Nighthawk AX3000 model: RAX40-100NAS router.

Some devices are wifi and others are hardwired to a switch box which in turn connects to the router.

My cable ISP lost its local contract.  This has allowed me to consolidate services, etc.  So I went with T-Mobile for both phone and internet service.

I now  have the T-Mobile Internet Gateway tower, but it has to be located in another room and I cannot cable it to the Nighthawk.

How do I set up the Nighthawk to communicate with the Gateway  without making any adjustments to the Gateway.

My main concern is for the hardwired devices to work.  The wifi devices on the Nighthawk can be transferred to the Gateway.  I cannot relocate the switch box or Nighthawk.

Would appreciate any guidance.

Thanks.