Hi. One welcome to the forum, good for you to try and start to change your body for the better.
Looking at your stats (weight, height,age) to stay at your weight level you need to take in 2000 calories a day. So to lose weight you take away 500 calories. It takes 3500 calories to lose 1 pound. So hey your thinking great i knock off 800 calories a day and will be there in no time. Doesn't work like that. No less than 500-600 calories cut. You do more than that and all that fat you want to lose will suction itself to you cause its afraid you are not going to get food anymore. The body is smart, you can't trick it

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Now first thing first you can't spot reduce. Meaning you cant just lose weight on your belly and keep it on your ass. So basically you have to decide what you want more, a lean no saggy body with maybe a little less rump (and trust me the ass is the last thing to go anyway) or to stay the way you are. You can do 1000 crunches but if you aren't doing cardio and eating right it wont make a difference. So if you are ready to get in shape then keep reading and do the following, if not its okay it comes when it comes.
1-Don't try it all at once- You can't just go from fast food to spinach and brown rice over night. Its not easy i know. I went from hot dogs and fast food everyday with big glasses of sweet tea, to only drinking water and having a strong balanced diet. I am still in the process of losing fat, it takes time, but its not a diet, its a lifestyle change. Thats a big thing, so don't expect to be able to do it all at once. It took me a month to ween and get it right. But after i did i lost weight really healthy and pretty fast.
2-Make the time-You have to remember it took years to put that weight on, if you want it to come off and get your body toned in a short amount of time, then you have to double your efforts. You have to make the time to workout, you have to make time to eat right, you have to make time to learn what does what for you and your body. You have to make time to learn what to prepare and how to prepare it. People forget you can take food with you whereever you go. Pop it in a cooler..need to heat it up? there is a microwave in almost any gas station or rest stop/truck stop. Trust me it takes less time to stop and do that then to wait in a drive through window line.
3-Diet-with every meal you need one carb and one protien. The details of what however are most important. For protien...Protien shakes (low in fat and carbs) Lean meats (chicken, turkey, flank steak, fish, 96% lean ground beef) Try as much as possible for it to be raw items you cook, not processed pre-cooked slices in a package.
For Carbs-NO WHITE ANYTING! No white pasta, bread, sugar, rice, flour, anything like that. Whole grain products only if you must have bread. Sweet potatoes, brown rice, and of course veggies and fruits. Basically the closer it came from the ground the better it is for you to eat. Now again its a lot to take in and change, so do what you can at first but make these items be your ultimate goal in the end okay.
4-Water- Yes it gets a whole section on its on. Its the one thing people hear all the time but neglect its importance. Every meal you have....water. Inbetween every meal you have...water. You will have to go to the bathroom like a mad man, but its okay cause that water is flushing out everything bad you take in a day. At least 8-10 glasses a day.
5-Workout-Trainer lynns got you coverd there for sure.
6-Time-It takes time, lots of it. You will be frustrated and unhappy with how long it takes, how hard you are working and feeling you are getting anyhting back...but you will, trust me.
Good luck.