Use visual studio to solve the question C#

I have solved everything I want the calculation and the error handle. Please read the questions carefully and answer them correctly

The question

A fitness center wants to keep track on member's weight loss progress. Design and code a windows application for entering member information then analyze and display the Active Metabolic Rate (AMR). AMR is the actual amount of calories you burn each day due to physical activities like aerobics, yoga and so on. Knowing your AMR is essential in case you want lose weight, stay fit and healthy or gain weight.