If you don't already have a preferred IDE or text editor, add the Visual Studio module. Everything else is mostly for platform build support. I.E: You would include Android build support to publish on Android devices, Linux support to publish on Linux devices, etc. If you don't have any target platforms in mind currently, it's fine to just leave everything else unchecked. You can always modify your installation and add these packages later.
Yep, install VS unless you have a reason not to. Install the platforms you want to develop for. You can always reinstall later to add additional platform modules, so don't stress too much on it.
Here's where you can download the latest version of Unity Hub: https://unity3d.com/get-unity/update Edit, I just looked at the plans selection page and it looks like they changed it quite a bit. Honestly, it looks really messy.
There is no version of Unity for Chrome OS. A ChromeBook likely doesn't even have good enough hardware specs to handle large software such as a game engine either.