Hello. I can not code BMI in JavaScript. I want to get output without using alert, prompt,console.log but i just get bmi result [closed]

First of above thank you for spare time to read this. I am trying to code

function bmiCalculator (weight, height){
     return Math.floor(weight/Math.pow(height,2));
}

var bmi = bmiCalculator;


    if (Math.floor <18.5) {
        "your bmi" + bmi + "you are skinny";
    } else if (bmiCalculator<=10.5 && 24.9 > bmiCalculator){
        "your bmi" + bmi + "you are normal";
    } else {
        "your bmi" + bmi + "you are fat";
    }

but i stuck always in getting the direct result which is 15 - by the way i use var weight= 60 and height=2 for variation - Please teach me how to get return with if statements. 2nd question: I need also get if output without using alert,console.log,prompt. Is there a way ?