I make no money from photos.
I do them because I like. Mine started out with a love of wildlife and wanting to capture its images. I do shoots for free. I've had a couple of model shoots. They've bought me a costa and added my images to their portfolio.
Practice and money.
Better body with full frame has less noise, but costs
Better lenses with lower Fstops, but costs
Learning the lighting situations.
Editing in post.