Here are some helps:
Connecting The Onefinity CNC To A Network
This next one says it connects with HDMI but the writeup is all about ethernet. I have never done this but I’m sure it’s doable.
How To Connect To The Onefinity Controller Without A Screen Directly Connected Via The HDMI
Here is another one on direct connection.
How to directly connect your Onefinity CNC to a computer/laptop (no screen present)
One thing that sold me on the onefinity is there were so many ways to connect to it.
I had to use the onefinity supplied screen at first to get the wifi settings put into the controller. After that I got a wifi extender for my shop and have connected with my laptop ever since.
I use the laptop to load files to the controller mostly. I have never had to use a usb stick yet. Keyboad and mouse work fine, all things on the controller are available to you.
I would not get rid of the 10.8" screen connected to the onefinity though. It is more convenient when you are standing there to work the play/pause button. ( it is not nice for typing on though )
Hope these help.