Epson WorkForce Pro EC-4020/EC-4030/EC-4040 Ubuntu 18.04 Setup – Step-by-step Guide
Hi! The Tutorial shows you Step-by-Step How to Install Printer Epson WorkForce Pro EC-4020/EC-4030/EC-4040 for Ubuntu 18.04 Bionic LTS GNU/Linux Desktop.
And the Epson WorkForce Pro EC-4020/EC-4030/EC-4040 Ubuntu 18.04 Installation guide includes also instructions on How to Get Started Scanning on Ubuntu.
Especially relevant: using the Epson Printer Utility Software, you can Check Ink Levels, View Error and other Status… on EPSON WorkForce Pro EC-4020/EC-4030/EC-4040 Series Printers.
Finally, to Get the Epson WorkForce Pro EC-4020/EC-4030/EC-4040 Series Printers Installed on Ubuntu Linux you need to Download and Install the Epson Proprietary Driver.

1. Launching Terminal
Open a Terminal window
Ctrl+Alt+t on Desktop
(Press “Enter” to Execute Commands)2. Updating Ubuntu Repos
Then Update Ubuntu Bionic Repositories:
This step is a precaution in case the sources are not Up to Date.
So if you prefer try first to Install it directly like shown here below..sudo apt update