If you install a widescreen monitor, your Windows 10 Pro will automatically detect it and adjust the display settings accordingly. You will be able to see more content on your screen and have more space to work with. However, some older applications may not be optimized for widescreen displays and may appear stretched or distorted.
If you install a software that makes your screen widescreen, it will change the resolution of your display. This can make your desktop appear wider and give you more space to work with. However, it can also make text and images appear smaller and more difficult to read.