It's not impossible but it's not a very realistic goal for the time frame if you aren't use to exercise or proper eating.
To get the maximum impact for weight loss from cardio, I'd suggest an IT or HIIT workout three times a week along with weight training two times a week. Of course you should also stay as active as possible, taking the stairs when you can, parking your car on the far end of the parking lot, etc.
If you want to lose 2 pounds a week, the doctor recommended maximum, then you need to get rid of 7000 calories a week. Most people suggest the easiest way to do this is to reduce your maintenance caloric intake (the amount of food you eat to maintain your weight) by 500 calories and to burn 500 calories through exercise or daily activity for a total of 1000 a day, 7000 in a week. If you're actively gaining weight you need to reduce your caloric intake further.
I'll be honest with you and tell you that I predict that if you do lose the weight, you'll gain it back afterwards. Weight loss is about raising your health, eating well, and just taking care of your body. If your goal includes the end being "I just want to look good for this event" you're setting yourself up for long-term failure.