To install git you may visit https://git-scm.com/downloads page and install. Before going to install you may first check using the
git --version command
Git Clone : The "clone" command downloads an existing Git repository to your local computer.
Their are three stages
Already git install your system you can check what is your "Username" and "Email"
git config --list --show-origin
git config --global user.name "Your Name Comes Here"
git config --global user.email you@yourdomain.example.com