I've helped lots of people in similar situations over the years, so I thought I'd offer just a little advice.
I think the most important thing is to enjoy the whole process of losing weight. This may sound obvious, but if you are on a nutrition plan that is very restrictive, then you will end up resenting it and maybe quitting. I would ensure that you learn some basics about food and have an understanding of portion control, that way you can eat healthily yet still eat the foods you enjoy.
I would also pick a form of exercise that you like doing. I personally think weight training is the best way to lose weight, but you could supplement that with dance classes, long walks, a martial art or a sport. Anything that you enjoy doing that gets you moving will help.
Lastly, be patient. It may take you a year or two to get to where you want to be, so set yourself some mini goals along the way and focus on those smaller steps. Hope this helps.
If you would like to learn more about how I could help you on a 1-2-1 level, visit: http://www.bodysolutionslondon.com/services/personal-training-shoreditch-london.html