I've been searching for hours for help and just can't figure this out.

I have hardware version 1.20 and the latest firmware.

I have a Verizon Fios router as my main router and want to use the AX1500 as a bridge to my office so I can plugin things that require Ethernet access, like my NAS.  I updated the firmware today and the router has an option for passthrough or bridge mode, but turning it on doesn't work.  I seach for "WDS" on router settings and nothing comes up.  There are no WDS options on the wireless settings pages for 2.4 or 5 band.  I cannot find way to search for my main router to select for the bridge.

It is actually possible to do this?  

Thank for you for any and all support because I'm going crazy reading support docs and forum posts that don't seem to match up.