Hello! I’m also new to linux so I can’t answer you directly, I just can tell you how I did it…
I’ve installed WinSCP in my computer and from there I can transfer the roms to the Pi.. check your IP in the PI with “ifconfig” and put that IP in the connection you’re going to create with winSCP while choosing SCP connection…browse to the folder and paste them…
Sorry for not answering you directly and hope this helps
My issue seemed to be centered around the install directory of retropie, for some reason during my first install attempt it installed itself (although it was missing a lot) to the home/root/… directory.
My issues appear to be solely based upon the folder locations being inside of root (which must have been my error)
I reinstalled retropie again after updating the setup script and everything was installed to the correct /home/pi/…. directory.
I could ssh into the pi and access the root folders but was still unable to add roms. Now that the install is in the correct folder I have no problem adding them to the correct folders especially through samba 🙂
Now I just have to deal with my blank black screen errors!