Visual Studio Team Services is an hosted version of Microsoft Team Foundation Server. It doesn't require any installation as it's already done by Microsoft itself.
In order to start using Visual Studio Team Services you need to create an account here by pressing the Free account button. It will redirect you to the login page. Use a Microsoft account or, if you don't already have one, create it.
After you have logged in, you will be in front of this page: This will allow you to create a new team. Insert a project name and choose between Git and Team Foundation Version Control as version control system. By pressing the "Change details" you can select a different location for you project and the "work organization" type. After you have provided the required information, press the Continue button.
Features and pricing details can be found in the Remarks section