Hi, I have a Archer MR550 sim card router that I have wired into my house network. I have also run a cat 8 wire to my garage where I wanted to extend the wireless network too, so that I can pick up the network outside.the property,  I purchased a mesh extender RE450 that I hoped would do this. the RE450 has a rg45 connector socket on the side can I connect this to my wired network to use it as an extender ? or is the socket only for using as an output socket ? .

I am slightly confused when I see that you can switch the RE450 to access point mode, I did this but then the wifi didnt work off the unit, I have to log into it as an extender. whereas when used in mesh mode it links seamlessly.

Whats the best way of achieving a range extender with mesh capability if its possible.