Lots of good advice in the posts above, and a good book suggestion.
However, that being said, practice, practice, practice and more practice.
Take a Photography 1 class if you can. Learn how to shoot with a basic film camera with no automatic settings if you don't already know. This will help understand how all the functions correlate. The class will probably go over many lighting techniques. Things like how to light from a window, how to multiple light (with flashes or reflectors), even how to light subjects with a single candle.
And, yes, a large softbox will produce softer (IOW more evenly distributed) lighting when it is close to a subject than when it is a several feet away (given the same camera settings and flash settings). The farther away a softbox light source is away from a subject, the more it becomes a point source light (like the sun).
HTH.