Hi,
There isn't such a thing as becoming healthy rapidly!!If you change your lifestyle habits then you will see the benefit pretty soon.ONE-write down everything you eat in a note book(no cheating!!)so you are aware of you daily intake,TWO-exercise!!join a gym so you talk to a fitness instructor to have a program that fit your need.THREE-stop smoking if your a smoker.
Every little help,even a stroll around the block makes a difference,or extracting one food for a other,ie,skimmed milk instead of full fat milk.The principal are simple,EAT LESS,MOVE MORE,and be selective in your food,fruits,vegts,proteins,a little fat,little booze-moderation is the key.
Now if you are in a hurry-fast for two days,only water and you should see result straight away!!!Not a long term solution!!!
All the best,be patient,it will happen.