These are typical for ISA network cards but not universal. In case of doubt, find the manual for your NIC card. But of course you've long since thrown it away, so power down the computer, pop out the card, get the manufacturer's name and any identifying numbers, and hope you can find that info on the web somewhere. The other thing you might find on the web is the DOS program that allows you to reconfigure the card and change these numbers. If the card has more than one network connector, make sure the RJ-45 connector is selected.
Nobody uses coax any more.
Later I replaced the Intel NIC in richard with another Linksys card. I'd been getting error messages that were traceable to the Intel card, and Linksys has been in the networking business a long time and seems to make quite reliable stuff. Decide what IP addresses all your boxes will have There are magical ranges of IP addresses. IP address space is NOT a breezy forgiving tabula rasa, it is mined with hideous treacherous traps. For a home intranet that doesn't connect to the outside world, you want to use addresses from 192.168.0.0 to 192.168.255.255.