add/remove inputs/buttons

HTML

<div id="reqs">
  <h3>Requirements</h3>
  <button type="button" value="Add" onclick="javascript:add();">Add</button>
  <br>
</div>

JavaScript

function removeElement(e) {
    let button = e.target;
    let field = button.previousSibling;
    let div = button.parentElement;
    let br = button.nextSibling;
    div.removeChild(button);
    div.removeChild(field);
    div.removeChild(br);
    
    let allElements = document.getElementById("reqs");
    let inputs = allElements.getElementsByTagName("input");
    for(i=0;i<inputs.length;i++){
    	inputs[i].setAttribute('id', 'reqs' + (i+1));
    	inputs[i].setAttribute('value', (i+1));
      inputs[i].nextSibling.setAttribute('id', 'reqsr' + (i+1));
    }
  }
  
  function add() {
    let allElements = document.getElementById("reqs");
    let reqs_id = allElements.getElementsByTagName("input").length;
    
    reqs_id++;
    
    //create textbox
    let input = document.createElement('input');
    input.type = "text";
    input.setAttribute("class", "w3-input w3-border");
    input.setAttribute('id', 'reqs' + reqs_id);
    input.setAttribute('value', reqs_id);
    let reqs = document.getElementById("reqs");
    
    //create remove button
    let remove = document.createElement('button');
    remove.setAttribute('id', 'reqsr' + reqs_id);
    remove.onclick = function(e) {
      removeElement(e);
    };
    remove.setAttribute("type", "button");
    remove.innerHTML = "Remove";
    
    //append elements
    reqs.appendChild(input);
    reqs.appendChild(remove);
    let br = document.createElement("br");
    reqs.appendChild(br);
  }