Where do I belong[Solved]

Code Feedback
1

What do you think of my solution? I just wanted to make sure I had the right idea of solving it.

function getIndexToIns(arr, num) {
   
  arr.sort(function(a,b){
    return a-b;
  }); 
  
  arr.push(num);
  
  function finditsplace(x){
    return x >= num;
  }
  
  return arr.findIndex(finditsplace);
}
getIndexToIns([3, 10, 5], 3);//0