HOW TO SPLIT SCREEN MAC
Select System Settings from the Apple menu at the top left corner of your screen. On older versions of macOS, choose System Preferences.
Select Desktop & Dock from the sidebar, then scroll down on the right and make sure that "Displays have separate Spaces" is turned on. On older versions of macOS, you can find this setting under the Mission Control menu.
Open an first application you'd like to split screen, then click and hold the green button at the top left of the window. This is known as the full screen mode button.
Select "Tile Window to Left of Screen" or "Tile Window to Right of Screen" from the drop down menu.
The window then fills that side of the screen.
Click a window on the other side of the screen to begin using both windows side by side in split screen mode.
Use Split Screen Mode
Now that you are in Split Screen View, here's how to use it:
● To choose a window to work in, click anywhere in that window.
● Show the menu bar by moving the pointer to the top of the screen.
● Swap window positions by dragging a window to the left or right side.
● To adjust window width, drag the vertical line between the windows.
● You can switch to other apps or your desktop using Mission Control. To access Mission Control, press the F3/Mission Control button on your keyboard.
● A Multi-Touch gesture such as swiping left or right with three or four fingers on your trackpad can also be used to switch between apps.
Exit Split Screen Mode
To exit Split View, click the green full screen button at the upper left corner of either window. If you no longer see your other window, it may be hidden in fullscreen mode. Use Mission Control or swipe left with three or four fingers to locate the second window, then click the green full screen button to exit full screen mode.
Mac Split Screen Alternatives
If you want more capabilities than Split View mode offers on Mac, there are variety of third party split screen apps. These allow you to have have more than two apps split across your Mac screen. A popular split screen app to consider is Magnet. This app lets you open windows in sixths and adjust split screen view in numerous ways.