Ok you have like a problem with the windowed screen. I just changed the settings to be a windowed screen just to see how it would look like and now it's so damn big that I can't see much. And to make things worse I can't change it back to full screen because it's so big it doesn't allow me to reach the 'apply' button to change it back to full screen and now it's just stuck in windowed screen.
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When you select the windowed option you should also set the Resolution to something smaller than your screen before pressing apply so that that doesn't happen.
You can still move the cursor around with the keyboard to reach the apply button, but if that doesn't work, maybe you can try delete the options file and restarting the game. The options file is at "C:\Users\<username>\AppData\Roaming\Labyrinth of Legendary Loot\options"