What should I do if OBS is open and my game is delayed?

Dear community. I hope you are all doing well in these strange times. I have a problem with OBS. When I have OBS open on my desktop, my games are delayed. (e.g. In Minecraft: I click the left mouse button and my screen only reacts about 0.5 seconds later) Can someone explain to me in detail what I could do?

When you stream you always have delay. Or do you mean if you only have OBS open that you also have delay?

Even if I have OBS open, unfortunately it starts