QGIS is a free and open source geographic information system (GIS) that we can use for various spatial data management and analysis tasks for different fields, such as geography, environmental science, disaster management, urban planning, climate science, and many other fields that use spatial data. The strength of QGIS lies in the fact that it is an open source platform coupled with different plugins available for computing different tasks.
QGIS can be installed in different operating systems such as Windows, Mac, Linux, Android, and so on. QGIS can be installed from the following site:
http://download.osgeo.org/qgis/win64/
After going to the previously mentioned website, we will scroll down and click on QGIS-OSGeo4W-3.2.2-1-Setup-x86_64.exe to download QGIS 3.2.2-1 (or click on the installer relevant to the operating system you are using):