The game UI consists of widgets and windows.
When a window opens, screen reader will read its title and the first control within the window will become focused.
You can move focus to the next control within the window by pressing Tab, and to the previous one with Shift+Tab.
A window can usually be closed by pressing the close button in the upper right corner of the window, or by pressing the Escape key.
A lot of controls react to the arrow keys, letting you to change the value in the control and the Enter key to activate the control (for example, to press a button) or to confirm the selection within the control.