I suspect you are running an older version of OSX, what model is your Mac and what version of OSX are you running.
From the Apple menu in the corner of your screen, choose About This Mac. You should see the macOS name, such as macOS Big Sur, followed by its version number. Need to know the build number as well, click the version number and share that info.
Thanks for that information, you will want to try again by doing the following.
First, be sure that you have removed all Epson software from the computer. Second, Acquire the software and drivers for your version of macOS 11 here.
After getting that software installed if you are still having an issue, it would be best to get Epson support to assist.
Lastly, you said the Epson printer is working with the Windows PC, I assume this printer is networked. Is it on a hardwire Ethernet connection or is it connected wirelessly?
Thanks John!! It’s working now. Everything Kim says about you seems to be true! The printer is on the network wirelessly. Both computers are also on the network, iMac connected on Ethernet and Windows wireless.