Can't build to IL2CPP (No options for IL2CPP exists) Why is that?

I only have the scripting backend option for Mono. I would like to build to IL2CPP for code obfuscation. Any idea why this is missing?

I’m using Unity Version 2017.3.0f3

Did you install is when you installed Unity? I guess you didn’t ^^.

I would recommend you install the Unity Hub. There you can manage several Unity versions and edit / add components to the installation.