I have 1 swollen tonsil with no pain. it looks like there are blood spots or patches on the tonsil. i see 1 whitish patch also. infection or cancer?

Probably neither: A tonsil doing its job of protecting you form microbes can get quite large and nasty-looking. The prominent vessels are a sign that it's working hard. Everybody's got white patches on the tonsils. Only if it is clearly out of place should there be a cancer concern.

Get eval: Most likely an infection, cancer would be unusual to occur all of a sudden. Get eval to be safe, most likely treated for a possible infection, then if it persists, continue to get evaluation. Best wishes.