I would reccommend shooting in RAW and shooting on Auto White Balance. Then you can fix it in your RAW processor if need be

We want to get off the 'auto/green box' setting ASAP! It will make for 'worse' photos for the first couple of shoots but damn it will help in the long run!

If you shoot wide open AKA f/1.8 let's say you are looking at a very shallow depth of field. That means that the blades are 'wide open' and only what you focus on will be sharp and in focus, no much in front or not much behind. Only fast lenses will get down in the 1.8-2.8 range. Most lenses are 4+ and that isn't HUGE depth of field.

Landscape shooting you may shoot in f/8-f/11 and that will keep everything in sharp focus. This is letting in less light and thus will need longer exposures.

Aperture basically adjust the depth of field. I would recommend starting to shoot in Aperture priority and it allows you to choose your depth of field and the camera adjust the other settings