Keyboard navigation keys: Tab, Shift, Arrow keys, Alt, Spacebar, Enter and Esc. Google Search ‘microsoft using your keyboard’

Navigation key actions: Use Tab to move focus, Shift + Tab to change direction, Arrow keys to move selected option, Spacebar to reveal options or expand folder contect (disclosure button), Enter to action a selection (e.g. open a file), Alt to show hidden options available with keyboard keys and Escape key ‘Esc’ which is the same as clicking the ‘Cancel’ button or closing a menu without choosing an item

Select individual files: Choose the first file by navigating to it with the Tab and arrow keys then select by pressing Spacebar. Hold down Ctrl key (to keep selected) and arrow key to the next file. Press Spacebar to select until all individual files are selected

Select multiple adjacent files: Choose the first first by navigating with the Tab and arrow keys then select by pressing Spacebar. Hold down Shift then arrow key to the last. All will be selected