Hey @Ali, installing Git on ubuntu is pretty easy, just follow these steps:
log into SSH via root user
execute this command to update the repository
apt-get update
Install git
apt-get install git-core
Confirm the installation
git --version
configure git settings
git config --global user.name "user-name"
git config --global user.email "user-name-emai@whatever.com"
list configurations
git config --list
And you're ready :D