Samba Setup

Total super newbie - like 5 hrs… trying to learn how to network to my other Win 7, 10 and Android 10 devices from an ex-Win 7 that had hard drive failure five months after MS stopped Win 7 support. Finally got it running again and had issues with old Win 7 without service packs. So Ubuntu… whole new world for me at 71. My HP printer would not talk to the repaired Win 7 and this Ubuntu had no problems printing a test page… Now I need to do and then print old farts tax return and property tax exemption forms. Looks like I can put things on a usb drive but I also used this machine for 2 - 1TB backup drives that I ran across my wireless MS network. Ubuntu appears to read those data files OK.

Love the instructions but this newbie doesn’t even know how you get to
“To install Samba, we run:
sudo apt update
sudo apt install samba”

Where does the entry box come from and how to access it? Ubuntu 16.04