Im getting more and more chances fishing with my dad in his boat im just having a problem understanding how to fish open water points and flats using electronics.

I have an old Eagle 440 i think on the back of the boat and a new Hummingbird 550 on the front but i barely understand how to use them and im usually a quick learner with other electronics but i guess this is different.

Here's another bit of help for you.  Lowrance offers a free tutorial on reading and interpreting sonar images.

http://www.lowrance.com/en/Support/Tips-and-Tutorials/Sonar-Tutorial/