Introduction
This guide covers the basics of listing and searching for packages available for installation on Ubuntu 20.04 LTS.
NOTE: This guide assumes that you are logged in as the root administrative user.
Procedure
First ensure that you have updated your package information:
apt-get update
Then you can use apt-cache which formats it's output in a more compact way by default:
apt-cache search keyword
Or you may use apt, which adds color and has a more human readable format by default:
apt search keyword
They keyword that you use in the above commands is a regular expression meaning that you could just type the exact name of the package you want, only a portion of the name, or you could use the full regular expression syntax to perform an advanced search.
If you wanted to get the entire list of all available packages with either of these utilities, you could just use a period (.) character as your search term:
apt-cache search .
apt search .