I do not see what I paint, only when changing the brush I can see what I've painted, and so every time.
Your intel gpu driver is broken. Please tell us exactly which intel display chip and driver version you have, so we can tell Intel. In the meantime, you can work around it by disabling opengl in settings/configure krita/display.
Please tell us exactly which brand and model of system you have, and which version of display chip and display driver you have. For the driver version, press the Windows key, then type "Device Manager", open the Device manager application and check the Display Adapter dialog.
*** This bug has been marked as a duplicate of bug 360601 ***