How to pay for critical illness insurance

There are three ways to pay for critical illness insurance: the first way is to pay after diagnosis: it means that you can get compensation as long as you have been examined by qualified medical institutions and have typical clinical manifestations, and the diagnosis meets the definition of disease. The second category is the agreed conditional compensation, which is usually more complicated. First of all, the diagnosis results should conform to the definition of the disease and the additional regulations of the state. The third category is the agreed surgical compensation. This situation is generally related to important organs of the human body and requires some kind of surgical treatment. Which insurance company is better for critical illness insurance?