How do i do it is it possible?
Depending on the specific model, you can use it bridge mode.
Put sim card in phone and configure hotspot or if it's a modem, sambaza the inter to the zuku router (in bridge mode).
You can get a better WiFi range and ethernet connection via the Zuku router. I guess you will have to disconnect the coaxial cable.
Zuku routers have clanky and buggy old firmware (second hand from France) so... best of luck.
Report back if successful.