JSFiddle - React, Tailwind, and code Playground

HTML

<div id="sublist">

</div>

CSS

#navmain {
    display: block;
    width: 80px;
    height: 100%;
    border-right: 1px solid #999;
    background-color: red;
  }

  li {
    display: flex;
    flex-direction: column;
    justify-content: center;
    list-style-type: none;
    text-align: center;
    height: 80px;
    border-bottom: 1px solid white;
  }
  
  .selected{
    color: red;
  }

JavaScript

var data = [{
    sub: "home",
    row: "Home",
  },
  {
    sub: "home",
    row: "Test",
  },
  {
    sub: "code",
    row: "Code",
  },
  {
    sub: "prefs",
    row: "prefs",
  },
  {
    sub: "prefs",
    row: "User",
  },
];


filtered(data.filter(item => item.sub == ['home']))
filtered(data.filter(item => item.sub == ['prefs']))

function filtered(data) {
  data = JSON.stringify(data)
  alert("filtered "+data)
}