I think one skimmer will be fine but one of our installer members may think differently. I have a 27 ' pool and one skimmer. Hoses are typically bought separately and you'll probably have to get them from a pool store. I'm not sure if Lowe's or Home Depot sell pool sand. I haven't looked. Someone else will chime in here who may have looked recently.

You're getting closer to swimming! Very exciting!