I have been trying to lose weight in my thighs for months . I'm not a very heavy person but my thighs are extremely flabby and they have deep cellulite . I was wondering what's the cause and what I can do to get rid of them fast? Currently I have a gym membership and I can do both weights and cardio .

Cut out artificial sweeteners, anything diet, message, gmo, processed foods, prepackaged foods, junk foods and anything with a long list of other ingredients. Even many health bars are loaded with fattening junk

First... nothing that goes on slow will ever come off fast.

I'd talk with someone at the gym to recommend certain exercises to target the areas you need. THey can recommend how many reps... and sets on what equipment they have that you would be using.