How Do I Get Net Framework 3.5 For Windows 10 Enterprise

[Can You Help Me Please]

I need the framework for a specific program, but I've been everywhere and no luck. I just get a message saying "the following feature cannot be installed. The referenced assembly is not on your system.

 

[SkyNetRising]

Go to:
Control Panel/Programs and Features/Turn Windows features on or off
Check Microsoft .NET Framework 3.5 and press OK.

 

[Can You Help Me Please]

I did that and I still get an error