We're going to start using GIS next week. To get set up for that, please download and install the open-source GIS application QGIS. It's available here:
The download page will offer several versions that vary with your operating system.
Choose the QGIS Standalone Installer Version 3.10. You'll need to choose between the 64-bit and 32-bit versions. Pick the 64-bit version: the 32-bit version would only be necessary if you had a very old version of Windows.
If you're running macOS 10.13 or newer, choose QGIS macOS Installer Version 3.10. If you have an older version the installation is a bit more involved because you'll need to install a specific version of Python. If you're in that situation and have any trouble, please get in touch with me.