Somehow I always have the feeling with my laptop that the game lags rather when the graphics settings are low, but if I put them to the maximum, it runs almost smoothly
A PC can't be under-challenged. Surely you do not confuse Laggs with Tearing?
What are tearings?
This happens when the graphics card sends too many images the second to the monitor and this does not come after. Then the monitor quickly shoves after the next picture and can look like Laggs.
Most of the problem occurs with High FPS + Monitor below 120Hz.
So you want to tell me that the computer at lower graphics setting in the game must send more pictures than at high?
No, but he just sends more
Not necessary but power. The higher you set the settings the less FPS you have automatically. And the lower you set the settings, the more FPS you have automatically.