Hi, you need a multidisciplinary approach. Dietician consultation, exercise and for irregular period you need to do some investigations. Weight reduction will take time. It's not immediate effect. You will need to start on tab. Metformin 500mg once a day, look for any nausea or vomiting trouble, if nothing after 7 days, then increase it to twice a day for 3 months. It will help in weight reduction. And diet consultation is must. Exercise, if possible join gym, or yoga or aerobics.
All the best!