During the game my FPS is around 58, how to increase it? I can't play like that, it's awful
I have just turned VSync off, and my FPS is now 450 Isn't it strange that with VSync it's only 60
It's not one, set number that humans can't notice beyond. Different intensities/shades can be noticed even if just shown for a few milliseconds in some cases, if I remember correctly. In general, more FPS means smoother game.
i play on 20fps and i feel okay
If your monitor is at 60 Hz (which it usually is), it doesn't matter if your FPS is 60 or 100. The game will render 100 frames per second, but your monitor displays only 60. Vsync tries to keep the FPS same as your monitor Hz.