CODE EXAMPLE FOR HTML

input group

<div class="input-group mb-3">
  <button class="btn btn-outline-secondary" type="button" id="button-addon1">Button</button>
  <input type="text" class="form-control" placeholder="" aria-label="Example text with button addon" aria-describedby="button-addon1">
</div>

<div class="input-group mb-3">
  <input type="text" class="form-control" placeholder="Recipient's username" aria-label="Recipient's username" aria-describedby="button-addon2">
  <button class="btn btn-outline-secondary" type="button" id="button-addon2">Button</button>
</div>

<div class="input-group mb-3">
  <button class="btn btn-outline-secondary" type="button">Button</button>
  <button class="btn btn-outline-secondary" type="button">Button</button>
  <input type="text" class="form-control" placeholder="" aria-label="Example text with two button addons">
</div>

<div class="input-group">
  <input type="text" class="form-control" placeholder="Recipient's username" aria-label="Recipient's username with two button addons">
  <button class="btn btn-outline-secondary" type="button">Button</button>
  <button class="btn btn-outline-secondary" type="button">Button</button>
</div>