QGIS is an Open Source (free to use) desktop GIS, in can handsel the needs of most Geospatial projects, although it is not quite as feature-rich as ArcGIS Pro. In addition to the built-in functionality, QGIS like ArcGIS pro can be extended by using the programming language Python. For QGIS many such extensions are packaged into so-called plugins.

Installing QGIS.

Installing QGIS is a bit more complicated than most programs, I have therefore created a little guide for the purpose (Installing QGIS)

Changing the User Interface Language.

It might seem strange to introduce this rather specialised QGIS topic, but QGIS has an in many ways recommendable approach to language so by default it uses the language of the system it is running on. However many learning resources are in English so it is probably easiest to learn QGIS by changing its language to English. This is explained in the Introduction to QGIS learning path

Introduction to using QGIS

You can find an introduction to QGIS learning path here.

Installing plugins in QGIS

Installing plugins is relatively simple (go to the plugins menu and chose Manage and install Plugins. If you need some extra help other is a more detailed guide here)