BEST websites for brain exercises for dumb people to become geniuses?

I am stupid and forgetful. I want to become smart and remember everything and be able to solve problems, think fast, cure cancer etc etc etc. What are the best websites that cover all areas of the brain, like memory, problem solving, and um, well I dont know the rest because I am dumb and need to know how to figure it out! Please help. ....PS I have no money, so dont send me links for sites like 'Lumosity" where you have to pay to become smart. Thank you!