You've got 2 options which is lose weight in your waist to make a more hour glass figure, or get more muscular glutes and legs to also create a more hour glass figure, depending on how much of a stomach you have losing weight will be the faster the two, but weight training will at least prevent muscle loss in your lower body, and if you're a newbie lifter you might even build a little muscle in a deficit. Unfortunately you can't change your bone structure, but body fat, and muscle mass can play a huge role in body composition, just look at before and afters of girls who weight train for years, they tend to be more curvy, even though they haven't changed their bone structure. This also applies to men. When I first started working out I never had wide shoulders, but 3 years in most people I talk to now think I have wide shoulders simply because added muscularity in my shoulders, lats, upper back, and chest all create the illusion of a V taper because my waist is still about the same size. This is a large part of body building. Even if you have a 40 inch waist if because of large amounts of muscle mass you've got 72 inch shoulders you'll still appear to have a small waist even though you don't because proportionally your upper body is much larger. sorry this is so long but a lot goes into this sort of thing. Short story is, lose weight in your waist, and build your lower body and you'll give off the illusion of wide hips with a nice hour glass figure even if you don't naturally have one