Playing a game in windowed mode makes it easy to switch between the game and other apps. Many games give you the option of running the game in a full screen window, but if you want the best of both worlds check out Andrew Sampson’s Windows program, Borderless Gaming. When you have it on your PC, just start a game in windowed mode…
…and you can toggle it to fullscreen in Borderless Gaming:
You’ll be able to play the game in full screen, yet still easily switch between applications as if the game was in windowed mode. Here’s a guide to using Borderless Gaming by YouTuber xxdrangoog:
You can download Borderless Gaming on Andrew’s GitHub page. It’s not guaranteed to work with all games though. Gamers have also pointed out that AMD’s Crossfire technology only works in full screen mode, so take that into account before using this program.