Learn GCSE Product Design (Explained)

Now I'm not one for having any idea for a realist job that I want to have in the future. I'm more like, this month I want to be a games creator! Now this week I want to push pigs down hill for a job! And one month I was all, I want to create merchentdise and awesome stuff! I have got a notebook slowly filling up with ideas as we speak, but I have no knowledge of any of there manufacturing, so I thought I'll start at the bottom, and if I enjoy it I'll work my way up to A level standard and so on. (Sad story is that I wanted to take A level Product Design but I really needed to of taken GCSE and I would be the only one, so it wasn't going to happen. Oh well.)