<input type="text" id="input" />  
<button onclick="capitalizeFirstLetter()">  
  Click
</button>
<h5 id="output"></h5> 
function capitalizeFirstLetter() {
  let input = document.getElementById("input"); 
  let Element = document.getElementById("output"); 
  let text = input.value; 
  Element.innerHTML = text[0].toUpperCase() + text.slice(1); 
}
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