Geekshop installation on my windows 10

Can anyone please help me I have been trying to install this on my machine for about a month and a half. The install instructions for this needs to really be updated. I have laravel and voyager installed on my pc under C:\xampp\htdocs\ and have the geekshop blog files in a different folder like so C:\xampp\htdocs\foldername... Now trying to run composer install inside C:\xampp\htdocs\foldername I get these errors...

example ......

[RuntimeException] Failed to clone https://github.com/thedevdojo/voyager-themes.git, git was not found, check that it is installed and in your PATH env.

'git' is not recognized as an internal or external command, operable program or batch file.

When I go download this file and unzip it, it looks as this voyager-themes-master and I placed it inside the resource folder as directions on Git say to. Can someone please help me I dont have the money to pay someone to do this and should not have to being I paid for it. I have little knowledge on doing this so any help would greatlly be appreciate and I promise I am very thankful for your help if anyone can please understand. Thankyou