I get white patches on the side of my throat. It is Painless and I can scrape it off. What could it be? It resembles cottage cheese appearance.

Food particles. You are probably getting tonsilliths. Which are food particles trapped in pockets or folds in your tonsils call crypts. They are only a problem if they cause bad breath or infections. You may remove them if they bother you.
Possible thrush. Needs clinical evaluation and probable microscopic examination. Could be fungal infection like candida. May need a medication like mycelex (clotrimazole) troch or nystatin. See an oral surgeon.