Why is the air pressure higher in winter than in summer and higher in sunny days than in cloudy days?

The first question: the mainland cools down more than the ocean in winter, so the atmospheric circulation rises from the ocean to the mainland to form a high-pressure mass, but it is the opposite in summer, so the air pressure in the mainland is higher in winter than in summer. The second question: It should be said that all places with high air pressure are sunny, because the cloud system moves from the high pressure area to the low pressure area with the movement of atmospheric circulation.