Does anyone knows a website where you give simple simple sentence and they give it back to in hard english but meaning the same meaning?
You won't make it if you don't even know what to start with. Make your own stuff, be original. Don't try and be like these awful rappers.
whats your problem and English? seriously if you want to become a rapper you dont have to have slang in it. just have rhymes and metaphors and WORDS. start it out as poetry then give it a beat and BAM you got a rap.
You could do that right here on Ask.
Look at the way other people phrase things. A lot of rules apply to a lot of things - once you've got the hang of it it becomes second nature.