You will need to install QGIS in order to complete this course. You can download this free, open-source software from https://qgis.org
We recommend installing the Long Term Release (LTR) version; currently 3.16.11 Hannover [November 2021]. The instructions on this course were written for QGIS v 3.16
We cannot provide help with installing QGIS unless you are on a paid course