JSFiddle - React, Tailwind, and code Playground

HTML

<h2>Header fixed</h2>
<br/>
<br/>

<table>
    <thead><tr><th>HEADER 1</th><th>HEADER 2</th></tr></thead>
    <tbody>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
        <tr><td>1. DATA</td><td>1b. DATA</td></tr>
    </tbody>
</table>

CSS

table {
    width:400px;
}

tbody {
    height:300px;
    overflow:auto;
    display:block;
}

thead {
    color:#000;
}