Adding a Mac using os9 to a PC network

I am not familiar with Mac’s at all and for something that I keep hearing is the easiest computer to use I can’t seem to get it to do anything I want it to do….I was given an IMac of course it is outdated but I wanted to add it to my home network and I can’t even get it on the internet using my broadband modem and router(s). Could someone give me some assistance. Thanking you in advance. I have a Windows network with 98, 2000, and XP on the network, the mac has appletalk and built in ethernet connection.