On your Mac, in the Printers section of the System Settings > Printers & Scanners panel, does your Epson printer appear there with a green active light, and the Default printer is set to it? Do not have the Epson printer connected to any computer with a USB cable as that will defeat AirPrint.
In Pages on iOS 26, tap the ⋯ on the toolbar and select Print. For Printer, tap the No Printer Selected. Does it show your Epson AirPrint printer there and allow you to tap on it for selection? That should set the default printer for you in Pages — providing it is correctly configured and powered from the first paragraph.