The real answer can only be provided to you by a health professional, but I can give you some things to consider and educate yourself on in advance. Do some research and have a serious conversation with your doctor.
You may already be experiencing insulin resistance. This means that your arteries are routinely being doused with fatty deposits that are binding to the walls and will stay there. As those walls get gummed up, the smooth muscles around your circulatory system constrict, increasing your blood pressure.
The fact that your father already has type 2, and that you are already overweight lends itself to the idea that you are in a home with customs and dietary habits that are at odds with health.
I would really recommend watching some of the well made documentaries about food in the western world. The sad reality is that the average American is very out of touch with what they should be eating. You most likely need to completely change how you look at food, your body, and health.
It's not optional either. You either make time and effort towards being healthy, or you will spend time and effort dealing with the illness that make up metabolic syndrome.
Talk to your doctor. There are real concerns about rapid weight loss, so you'll want to be monitored. Plus, you're going to love having hard data showing how much progress you've made.
Focus on nutrition over everything else. It is extremely hard to burn a few hundred calories, but it is much easier to not eat them in the first place.
Start walking every day for 30 minutes. More so than the exercise itself, get in the habit about caring enough for your health that you prioritize. Do not short change yourself. Nearly every highly successful person in the world puts physical health on the top of the priority stack because without it you can't do much else.
Remember that it took a while to get fat, and it will take a while to get thin. Use a good plan, stay on it, and have faith in the plan.
Come back here and ask us any specific questions you have, we'll be happy to help.