Solved this myself since no one responded. Answers in case someone has the same issue:
RetroPie SD Imager has Rasbian OS included. Go to command prompt and type
In Rasbian you can use it to set up your wireless network.
With the Pi clocked to max and configured, certain games will run, but still with lag. The Pi just isn’t as powerful as the N64.
Using the WinSCP to edit files works the same as opening the file from within linux using nano or whatever tool.
Thanks goes to myself for figuring it out.