I’m not a personal trainer but in my experience you can lose weight proportionally to your body and not really do anything for spot treatment. Essentially, you will always keep your general shape (curvy, hourglass, narrow, etc) but just in different proportions.
That said, there have been studies conducted that conclude that gaining weight around the middle is unhealthier than gaining weight in the lower body. (In some groups this is called being “apple shaped” versus “pear shaped.”) If you happen to have more “flab” in the abdomen you are most likely storing fat everywhere else — otherwise known as “skinny fat.”
The best course of action from my experience as a casual athlete is to modify your diet and exercise routine. Cardio speeds up fat loss if you hit the right target heart rate and protein builds more muscle if you consume the right amount. Exclude unwholesome items from your diet (i.e. white rice, white bread, junk food, sugar) and replace it with things that are higher in nutritional value (whole wheat pasta, black pearl rice, quinoa, beet sugar, etc). It’s the little swaps that add up to a lot in the long run. Don’t focus on making too many major changes all at once or you’ll end up at square one quickly.
Overall, *some* fat is normal and necessary. Rule out medical conditions first with your doctor and consult with a nutritionist or holistic health practitioner on the best diet and exercise plan for your body type and family history! You probably did not gain that extra weight doing one thing over and over…and you won’t lose it doing just one type of exercise, either.