Does "Jeden" com from "Jeder"? and it's written this way because it's in accusative? Jeder becomes Jeden?
yep. same way der becomes den
I'm wondering the same thing. That must be the case, otherwise "jeden" means "each"
Could one say: "You like everything."?
I think the correct sentence for that is "Du magst alles".
I don't understand. How do I know it is jeden when I have no noun?