Answer by Marc for How do I install my printer to ubuntu?

You need hplip, which can be downloaded and installed easily. It provides support for printing, faxing, and scanning (including duplex scanning and printing) for HP all-in-one printers. I have an 8620 myself.

Install HPLIP in Ubuntu/Linux Mint:

1. download HPLIP .run installer from: Download HPLIP

2. Open terminal (Ctrl+Alt+T) and run command to give executable permission to the installer:

   cd ~/Downloads/ && chmod +x hplip-*.run

3. Finally start the installer and follow the terminal prompts:

   cd ~/Downloads/ && ./hplip-*.run

Courtesy of Ubuntu Handbook.