JSFiddle - React, Tailwind, and code Playground

HTML

<select name="kategori" onChange="getData(this);">
     <option value="hat" onClick="">Hat</option>
     <option value="emlak">Shirt</option>
     <option value="vasita">Pants</option>
</select>
<select id="emlak" name="currentList" onChange=";" style="display:none;">
     <option value="hat">Hat</option>
     <option value="emlak">Shirt</option>
     <option value="pants">Pants</option>
</select>
<select id="vasita" name="currentList" onChange="" style="display:none;">
     <option value="hat">Otomobil</option>
     <option value="emlak">Shirt</option>
     <option value="pants">Pants</option>
</select>

JavaScript

function getData(dropdown) {
var value = dropdown.options[dropdown.selectedIndex].value;
if (value == 'emlak'){
document.getElementById("emlak").style.display = "block";
}
if(value == 'vasita'){
document.getElementById("vasita").style.display = "block";
}
}