Wifi Modem to Netgear AC1750 (R6350)

Hard Ver: R6350

Firm: Ver: V1.1.0.78

Attempting to connect Wifi Modem to Netgear Router. Currently using Netgear 4G LTE as modem which has a Ethernet Cable from modem to router. Has been working great but current internet provider will soon require use of a mobile wifi hotspot to provide internet. (Must use their propriotary device. Can handle up to eight wireless connected devices, but no ethernet cable port)

Is there a way to connect the wifi hotspot source wirelessly to the Netgear Router?

Internet search says to use a ethernet bridge. I have a netgear wifi range extender (WN3000RPv3) that I tried to test from Iphone Cellular Hotspot but could not figure out how to configure to test connection.

Any assistance would be greatly appreciated. Thank you.