Answer 1

function Func3(){
if(countEn >= 20){
// You need to subtract 20 from countEn and save that value back into countEn
countEn -= 20;
// Then you can just set 'energy' to that value and when 'energy' is clicked the value will increase as it should
document.getElementById('energy').innerHTML = countEn;
document.getElementById('coin').innerHTML = ++countMo;
}
}