<style>
body {background:#aaa; margin:0;height:100%;
}
#d_all {background:white;width:90%;margin-left:auto; margin-right:auto;margin-top:3px;margin-bottom:3px; height: max-content}
#d_left {width:195px;float:left;background:white;}
#d_right {margin-left:195px;background:white; min-height: 100%}
</style>
<div id="d_all">
<div id="d_left">
1<br> 1<br> 1<br> 1<br> 1<br>
</div>
<div id="d_right">
12<br><br><br><br><br>
</div>
</div>let inputCount = 1;
const btn = document.querySelector('.btn');
btn.addEventListener('click', () => {
document.getElementById('div1').innerHTML =
`<input type="text" name="text${inputCount}" class="form-control w-50"/>`;
inputCount++;
});