Adding a NuGet Package Source that requires credentials with VS2015

I am attempting to setup a NuGet package source that requires credentials.

Here are the instructions

I have the latest version of Visual Studio 2015 with everything up to date. I am aware of how to add a package source through the UI in VS2015, but you can't specify credentials when doing it this way.

The command they are asking me to run is:

NuGet Sources Add -Name "telerik.com" -Source "https://nuget.telerik.com/nuget" -UserName "<your login email>" -Password "<your password>"

I am aware that I need a nuget.exe to run this command, but there is a way to do this directly through VS without downloading anything isn't there?

If I download the NuGet.exe, open a command prompt and navigate to it to run that command will I then be able to see it from Visual Studio's NuGet Package Manager UI and access it from Visual Studio's NuGet Package Manager Console? I am confused on how it will integrate with Visual Studio's built in NuGet Package Manager.