1 - Click Right mouse button on desktop
2 - Open "Nvidia Control Panel"
3 - Go to > Manage 3D settings
4 - Find DSR - Factors
5 - Choose a DSR setting of your choice

1 - Find your game in steam library
2 - Properties
3 - Set launch options...
-window-mode exclusive

WARNING!!!
Changing resolution in game options can freeze the game. Try Alt+Tabbing for 2-3 times. If it won't help, close the game and add new parameters to launch.

for example (Ultra HD 16:9):

-window-mode exclusive -screen-width 3840 -screen-height 2160



Well done! Enjoy!