First, you may be asked if you want to download/save/run/open/start this file: if possible, download/save first and then (double)click the downloaded scan program to run/open/start it.
In Windows 10 and beyond, a warning may be given that the program isn't a verified app from the Store: click 'Install anyway' (don't worry, it will NOT be installed but only executed once).
Or you may be asked to confirm that you want to run this file: click 'Run'.
The scan program is started: click 'Start' to perform the scan.
Perform a scan on your own computer or first try the sample scan to see what kind of data is retrieved and what sort of advices are given.