what I want is in the second picture...
and what I tried is :
function addrow(id) {
divarea = document.getElementById("kanbanrow");
var btn = document.createElement("DIV");
btn.className = "col";
btn.innerHTML = "CLICK ME";
divarea.appendChild(btn);
}
<link href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/5.0.1/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-+0n0xVW2eSR5OomGNYDnhzAbDsOXxcvSN1TPprVMTNDbiYZCxYbOOl7+AMvyTG2x" crossorigin="anonymous">
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.0.1/dist/js/bootstrap.min.js" integrity="sha384-Atwg2Pkwv9vp0ygtn1JAojH0nYbwNJLPhwyoVbhoPwBhjQPR5VtM2+xf0Uwh9KtT" crossorigin="anonymous"></script>
<button class="btn btn-outline-success float-end" onclick="addrow(this.id)" id="addstation" type="button">İSTASYON EKLE</button>
<div class="container container-fluid" id="mainpage">
<div class="row float-xl-start row-cols-auto table-responsive" id="kanbanrow">
<div class="col-sm">
<button class="btn btn-outline-success" onclick="addtodo(this.id)" id="addtodo" type="button">KART EKLE</button>
</div>
<div class="col-sm">
<button class="btn btn-outline-success" onclick="addtodo(this.id)" id="addtodo" type="button">KART EKLE</button>
</div>
</div>
</div>
Moving from left to right in more the 12 columns is going to be a problem it is possible but it is going to lose form. The best way to keep form is to add code to scroll.
<!DOCTYPE html>
<html>
<head>
<link href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/5.0.1/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-+0n0xVW2eSR5OomGNYDnhzAbDsOXxcvSN1TPprVMTNDbiYZCxYbOOl7+AMvyTG2x" crossorigin="anonymous">
<style>
div.scrollmenu {
overflow: auto;
white-space: nowrap;
}
div.scrollmenu a {
display: inline-block;
}
</style>
</head>
<body>
<div class="scrollmenu">
<a class="col-sm">
<button class="btn btn-outline-success" onclick="addtodo(this.id)" id="addtodo" type="button">KART EKLE</button>
</a>
<a class="col-sm">
<button class="btn btn-outline-success" onclick="addtodo(this.id)" id="addtodo" type="button">KART EKLE</button>
<a class="col-sm">
<a class="row float-xl-start row-cols-auto table-responsive" id="kanbanrow">
</a>
</div>
<a class="col-sm">
<button class="btn btn-outline-success float-end" onclick="addrow(this.id)" id="addstation" type="button">İSTASYON EKLE</button>
</a>
</a>
</body>
</html>
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.0.1/dist/js/bootstrap.min.js" integrity="sha384-Atwg2Pkwv9vp0ygtn1JAojH0nYbwNJLPhwyoVbhoPwBhjQPR5VtM2+xf0Uwh9KtT" crossorigin="anonymous"></script>
<script>
function addrow(id) {
divarea = document.getElementById("kanbanrow");
var btn = document.createElement("A");
btn.className = "col";
btn.innerHTML = "CLICK ME";
divarea.appendChild(btn);
}
</script>