I have a lowrance hook 7 fish finder and don’t under stand it .. it shows fish on it at different depths ..I guess. I just don’t know how to use it. I only use the gps , depth and way points on it . I want to learn how to use it for crappie and bass fishing. I’ve been to bass pro shop and they couldn’t help me just wanted to sale me a 1000$ different one . Can someone please help me with this.