In the Unreal C++ course Ben frequently uses Intellisense to browse the available methods. That’s fine, but it requires the associated .h (header) file to be included in the .cpp file.
The remedy is either include all .h files in every .cpp, which should negatively effect compile times or read the documentation.
Not a big deal, but I did spend 24 hours fumbling with Intellisense trying to get it to display the hints. Nothing other than including the proper .h will fix it.