Follow the steps:
- Start Atom
- Select menu item `View -> Toggle Command Palette`
- Search for “clone”
- Select “GitHub: Clone”
- Enter the URL of the GitHub project you want to clone
- Click “Clone”
To know the URL to use, go to https://github.com, navigate to the repository you want to clone, click the “Clone or Download” and copy the URL. You can choose between HTTPS and SSH, I would generally advise to use SSH.
I work as a freelancer, so if you don’t want to do that kind of things yourself or don’t have the time, just drop me a line to hire me.