What are these red dry skin patches on my cheecks?

Many possibilities. It could be any of many diseases such as lupus, acne rosacea, etc.
Actinic keratosis. An actinic keratosis (ak), also known as a solar keratosis, is a small, rough spot occurring on skin that has been chronically exposed to the sun. Actinic keratoses generally measure in size between 2-6 millimeters in diameter (between the size of a pencil point and that of an eraser). They are usually reddish in color, with a rough texture and often have a white or yellowish scale on top.