Answers for "onchange funcition in image input html"

js select on change value

document.getElementById('my-select').addEventListener('change', function() {
  console.log('You selected: ', this.value);
});

change src with inpute type="file"

<img id="output" src="" width="100" height="100">

<input name="photo" type="file" accept="image/*" onchange="document.getElementById('output').src = window.URL.createObjectURL(this.files[0])">