Try looking in SolidWorks help under planes (or look for reference geometry). Although a bether exercise would be to fix your sketch (you will learn much more).
You can make a plane parrallel to an existing plane/face at a specific distance. Try play around in the Plane feature to see what you can do.
You could also use Move/copy bodies to move the whole part but that's kind of cheating..
The easiest way in your case would be to :
selecting the plane you want the offset on and then
while holding the control key doing a left click on that plane and do a drag in the direction you want the new plane to be
in the feature manager you can define how much the distance between the original and the new plane should be
Have a nice one