If the notification is still active and on display, WinKey+Shift+V. Repeated presses should continue cycling through older notifications, but it's usually simpler just to go to the Action Center.
Otherwise, follow Mr. Maher's instructions and access your notifications list in the Action Center with WinKey+A
Brian - Windows 10 Pro, 64-Bit, Version 20H2, Build 19042
Any idiot can face a crisis. It's the day-to-day living that wears you out.
~ Anton Chekhov