Is 12 months enough to lose nearly 40 kg weight?
Its a very realistic goal and absolutely possible. The secret to weight loss isn't what most people will tell you, its not a pill, its not regular workout, its not diets we come up with everyday. The real secret is consistenty and gradual tweaking of your unhealthy lifestyle.
If somebody tells you to do something for 12months to lose 40kgs, it is not how that works. You need to climb that ladder slowly and steadily.
Start with minor modifications like lesser carbs, no binge eating, more water intake, 40 minutes of functional exercise, better sleeping patterns and setting short term goals.
With every step you take, you see more clearly what is to be added and how far it can take you. Never give up and all the best.