JSFiddle - React, Tailwind, and code Playground

HTML

<table>
    <tr>
        <td>
        <div id="test">этот текст должен быть всё время сверху</div>
        </td>
    </tr>
    <tr>
        <td>
            <div id="scroll">
                <table>
                <tr><td>aaa</td> <td>bbb</td> <td>ccc</td></tr>
                <tr><td>aaa</td> <td>bbb</td> <td>ccc</td></tr>
                <tr><td>aaa</td> <td>bbb</td> <td>ccc</td></tr>
                <tr><td>aaa</td> <td>bbb</td> <td>ccc</td></tr>
                <tr><td>aaa</td> <td>bbb</td> <td>ccc</td></tr>
                <tr><td>aaa</td> <td>bbb</td> <td>ccc</td></tr>
                <tr><td>aaa</td> <td>bbb</td> <td>ccc</td></tr>
                <tr><td>aaa</td> <td>bbb</td> <td>ccc</td></tr> 
                </table> 
            </div>
        </td>
    </tr>
</table>

CSS

#scroll{
    height:100px;
    overflow: auto;
} 
#scroll table {
    width:100%;
}
td{
    border:1px solid #000;
}