Install QGIS on Ubuntu
QGIS is an open source program which allows you to: "edit, visualise, analyse and publish geospatial information on Windows, Mac, Linux, BSD and mobile devices. For your desktop, server, in your web browser and as developer libraries."
To install QGIS 3.10 (Long Term Release, A Coruña LTR) on Ubuntu 18.04 (bionic) or Ubuntu 20.04 (focal) follow this guide:
NOTE: Follow the guide, but under "Add the QGIS repo ...". It will install the Latest Release, so to get the Long Time Release, you have to manually define the repo version.
# DON'T DO THIS: sudo add-apt-repository "deb https://qgis.org/debian `lsb_release -c -s` main"
In stead, edit the sources file directly. If you have Sublime Text installed, you can open the file with this command:
Add this at the bottom to allow access for the QGIS repository Ubuntu, and save:
deb https://qgis.org/ubuntu-ltr bionic main deb-src https://qgis.org/ubuntu-ltr bionic main
For Ubuntu 20.04, insert this in stead:
deb https://qgis.org/ubuntu-ltr focal main deb-src https://qgis.org/ubuntu-ltr focal main
sudo apt update, etc.
The QGIS training manual is a great introduction. Also, some videos based on the manual exist, though it seems like some steps are missing here and there: GIS 101: a complete tutorial for QGIS3.
Training Data: https://github.com/qgis/QGIS-Training-Data