Ok first step due to you not being able to unzip the file is:
Go to
https://www.7-zip.org/
you will see Download 7-Zip 19.00 (2019-02-21) for Windows:
download the 32bit version if you have 32bit windows
or
download 64 bit version if you have 64 bit windows
To see if you have 32bit or 64bit windows do this
Right click on the start menu (the window icon bottom left of your screen)
Click on System
Under Device Specification you will see System Type. Here you see what version of windows you have
Mine says 64bit operating system x64-based processor
Install 7-Zip