My hair is a white/blonde on the top half, and the bottom half is a dark brown, I want my hair to grow & I'm sick of dying it, I want to dye it all one colour, like a light brown, but if I do this at home, will my blonde go a light brown and the dark bottom half go a dark brown, how can I make it all one colour without going to the hairdressers or constantly dying it?

No chance of achieving this without going to a professional I'm afraid.

My mother is a professional, and you can achieve this, but the blonde will turn out a Gold-ish color, and you might miss spots with brown, Go to a professional and it will lookk great. (: