<div class = 'container'>
 <div class="helper"> 
 
 <ul class='list'>
 <li class = 'item'>1</li>
 <li class = 'item'>2</li>
 <li class = 'item'>3</li> 
</ul> 
 </div>
</div>

.container {
  height: 200px;
  overflow-y: auto; 
  background-color: lightcoral;
}

.helper {
   display: flex;
  align-items: center;
}
.helper > :first-child {
 margin-right: 20px;
}

.list {
  list-style: none;
  margin: 0;
  padding: 0;
}


.item {
  height: 40px;
  width: 100px;
  border: 1px solid black;
}