I want to do the two half circles... how can I do them?
I can do the rest without problem..
You can use the Arc Tool for example - or the Ellipse Tool (and cut the part which is not needed with an rectangle) or …
use Pathfinder Panel and Direct Selection Tool to select and remove unnecessary parts
create a duplicate of the arc with Mirror Tool and drag it a little bit downward
Why do I keep getting the extra line above when using the pathfinder?
Which pathfinder operation did you use?
But anyway, click with Direct Selection Tool on the line and delete.