I need help with my 'simple' roof

The only way to do this right is to do it the old fashion way of drawing the elevations on each side aligned to that side of the plan. Once started you decide on your slopes and start layout out each elevation which in turn starts "lining up to the other elevation". You then project lines over to the plan for your roof layout.

I have 4/12 and a 6/12 slope lines on the new roof (orange) to see which works/looks better. As you can see from the projected orange line one old roof line is already off.

You either do it this way or you do it in 3D.

Oops, forgot to draw in the 45deg lines are the corners.

Make no mistake, it will take some trial and corrections to get it right but it does work.

Or have SketchUp and the Instant Roof Tool plugin do it for you

you're the best

yeah i was suppose to change the rooms and stuff.. thanks though guys. and i'm a girl