

At least the lathe isn’t running punch tape.
Don’t upgrade or mess with the control. Disconnect from the network if it’s on it. It should have RS-232. Throw a Pi or other SBC that does serial and a 12V level shifter; use that to feed it programs.
Also, make an image of the hard drive if it has one and start looking for a spare drive on ebay.
Rock and roll. I’ve seen bad things happen when someone decides it’s a good idea to modernize a PC based CNC control. (I hate PC based controls). They get their own little fence to live inside where it’s always 1999.