The keyboard-shortcut that shows the suggestion menu with the necessary using statement is Ctrl - . or Alt - Shift - F10. The using statement appends to the top of the file after selection.
Here is an example of adding using System.Collections.Generic; after declaring List<string> variable.
Checked on Visual Studio versions:
- Visual Studio 2019
- Visual Studio 2022
You can always setup your custom shortcut Menu Tools -> Options -> Environment -> Keyboard -> View.QuickActions(View.QuickActionsForPosition)
You may be also interested to read my short-guides related to Visual Studio: