I REALLY wish this forum made members indicate what country they are from in their profile!!
So all I can do is advise you from a US perspective and that would be the same as @Iceman. As long as you have a HS diploma or a GED any community college or trade school will be happy to take your money. No questions asked.
Chefs are intelligent people, but most of us aren't "academics". Remember the only thing school grades determine is how good you are at taking tests. They're not a mark of your intelligence, nor do they dictate your future level of success. Once you find your passion, you'll excel. If it's what you really want, go for it.