What is the best way to learn about good lighting and composition without having a lot equipment?
Dear Follower, I would suggest using a lot of indirect daylight, inside(!) and outside; and then playing around with a sun bouncer (there are affordable bouncers on the market as well) in white or silver (gold is unnecessary, it makes everything golden and unnatural!) to brighten up the dark side of the faces or to catch sunlight and bounce it back onto your subject.
About composition… please photograph patterns, photograph building fronts, look where rays of light and shadows meet and make them appear beautiful. Go and capture faces (and crops of faces) in order to show what’s most important to you.
Take many many photos, sort out the ones you love and try to find out why, what’s different about their composition than the others’. Always frame in-camera, never later on the computer, or it will destroy your lens’ perspective.