You have to unpack a GZ file
The extension "GZ" stands for "GNU zip", a license-free compression Tool.
- Download the free (Ent)pack program "7-Zip" and follow the installation instructions.
- Then open 7-Zip and upload the GZ file of the Software. Then press the Button "Unzip".
- Now you just have to enter a target path and Unpack start.

With 7zip you can unpack .gz files
As you, yourself, create ZIP files, you will learn in this Short guide.