<div class="container">
  <div class="flex-gap box">
    <div>1</div>
    <div>2</div>
    <div>3</div>
    <div>4</div>
    <div>5</div>
    <div>6</div>
  </div>
</div>

.container{
    width: 500px;
    margin: 20px auto;
    border: 5px solid grey;
}

.flex-gap {
  display: flex;
  justify-content: center;
  gap: 10px;
}
.box > div{
  background-color: pink;
  padding: 20px;
}