Question

How to I do BMII am having difficulty do it

Answer 1

The BMI as in the Body Mass Index in order to find it you must know your weight and your height

Answer 2

To solve BMI 
1.) Take your weight and divide it by your height in Kg
2). You divide your answer you got in 1.) by your height.
3:) You get your BMI

*** Remember to do your height in Meters.