One month in Spain/ Hands On Cooking Teacher (Madrid)

Hi, I am food and travel writer traveling to Spain for one month in October. I will spend 8 eight days in San Sebastian. but the rest of the month is flexible. Can you recommend places I should not miss? I will be flying in and out of Madrid. Apart from San Sebastian, I plan to hit Bilbao, Barcelona, Madrid, any other recommendations. If there's a internations event pertaining to food, fitness, or walks, or exploring around Madrid. I'm trying to keep my expenses low. Can you recommend cheap accommodations or places happy to host a journalist/blogger? Last question, do you know of great hands on one one one cooking lessons preferably with a traditional Spanish cook? thanks!