Open the first window you want to use
Press Windows key + Left Arrow or Windows key + Right Arrow to snap it to one side
Select the second window from the remaining open apps
Press Windows key + Left Arrow or Windows key + Right Arrow to snap it to the other side
Drag a window to the left or right edge of the screen to snap it manually
Use the Snap Assist panel to choose another open window for the empty side
Drag the divider between windows to resize each side
Press Windows key + Up Arrow or Windows key + Down Arrow to adjust a snapped window
On Windows 11, hover over the maximize button and choose a split-screen layout
Select the window positions from the layout options
Repeat with more windows if using a multi-pane layout