JSFiddle - React, Tailwind, and code Playground

HTML

<select name="sel"> 
        <option value="o1">option1</option>
        <option value="o2">option2</option>
    </select>

    <select name="sel"> 
        <option value="o1">option1</option>
        <option value="o2">option2</option>
    </select>

JavaScript

document.getElementsByName("sel")[0].value="o2";