iPad and iPadOS don't natively support a wired (USB) connection to printers, but instead uses Apple AirPrint for printing wirelessly to compatible printers:
Apple AirPrint is a driverless connection protocol. A high proportion of modern printers intended for Home, SoHo and Business environments now support AirPrint. Check your printer model against this list:
About AirPrint - Apple Support
If your printer does not support AirPrint - there are limited alternatives…
Some printer manufacturers have a suitable companion App that provides Print capabilities for mobile devices, often using a web-based print service. Others can print directly if the App supports other network printing protocols. By example, some HP Printers use the HP Smart App - available in the App Store. There may be a suitable App for your sublimation printer supplied by Epson.
You might also consider connecting a non-AirPrint printer to a Windows PC or Mac computer - and install a “helper application” that allows the computer to emulate AirPrint capabilities.