my printer doesn't work anymore after installing big sur

Sometimes during updates some info is lost, probably because you don’t need to use it.

Try printing what you need to print, while doing that look at the settings for printing. Does it say it’s connected to your Mac? If it doesn’t, then follow these steps:

1) add printer

2) put in admin’s details

3) connect (easier with wires) your printer to Mac

4) the name should appear

5) follow the steps the Mac gives you.

depending on the model then epson may not have a big sur driver yet or plan not to make one if it's an older model

this is an example of how one use their site to check for drivers

Epson XP-15000 | XP Series | Single Function Inkjet Printers | Printers | Support | Epson US

if they don't plan on supporting the model then your options are

downgrade macos to a version they do support

or get a new printer which do support big sur

alternative if the model support airprint apples generic printing interface that may still be an option in terms of printing using that rather than their homecooked driver.