вы можете просто определить боковую панель в полную высоту с помощью маленького css, именно так:
.sidebar-row{
min-height: calc(100vh - 56px);
}
(это 56 пикселей - текущая высота заголовка) .. см. Пример ниже:
.sidebar-row{
min-height: calc(100vh - 56px);
}
.sidebar-row > *{
border: 1px solid red
}
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.1/css/bootstrap.min.css" integrity="sha384-VCmXjywReHh4PwowAiWNagnWcLhlEJLA5buUprzK8rxFgeH0kww/aWY76TfkUoSX" crossorigin="anonymous">
<div class="container-fluid">
<!-- header navbar -->
<header class="row">
<div class="col-md-12 nopadding">
<nav class="navbar navbar-expand-lg navbar-dark bg-dark">
<a href="#" class="navbar-brand">COMPANY NAME</a>
<button class="navbar-toggler" data-toggle="collapse" data-target="#navbarMenu">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarMenu">
<ul class="navbar-nav ml-auto">
<li class="nav-item"><a href="#" class="nav-link">Login</a></li>
<li class="nav-item"><a href="#" class="nav-link">Home</a></li>
</ul>
</div>
</nav>
</div>
</header>
<!-- sidebar section -->
<section class="row sidebar-row justify-content-start align-items-stretch">
<div class="col-md-2 sidebar-col nopadding">
<!-- <div class="wrapper h-100 my-wrapper"> -->
<nav id="sidebar">
<div class="sidebar-header">
<h6 class="sidebar-head">Functionalities</h6>
</div>
<ul class="list-unstyled components navbar-nav sidebar-un-list">
<li class="active nav-item sidebar-list">
<a href="#homeSubmenu" data-toggle="collapse" area-expanded="false" class="dropdown-toggle">Home</a>
<ul class="collapse list-unstyled" id="homeSubmenu">
<li class="sub-list">
<a href="">Home1</a>
</li>
<li class="sub-list">
<a href="">Home2</a>
</li>
<li class="sub-list">
<a href="">Home3</a>
</li>
</ul>
</li>
<li class="nav-item sidebar-list">
<a href="#">About</a>
</li>
<li class="nav-item sidebar-list">
<a href="#">Contact</a>
</li>
<li class="nav-item sidebar-list">
<a href="#">Help</a>
</li>
<li class="active nav-item sidebar-list">
<a href="#homeSubmenu2" data-toggle="collapse" area-expanded="false" class="dropdown-toggle">Home</a>
<ul class="collapse list-unstyled" id="homeSubmenu2">
<li class="sub-list">
<a href="">Home1</a>
</li>
<li class="sub-list">
<a href="">Home2</a>
</li>
<li class="sub-list">
<a href="">Home3</a>
</li>
</ul>
</li>
</ul>
</nav>
<!-- </div> -->
</div>
<div class="col-md-10">
Hello
</div>
</section>
</div>
<!-- container-fluid ends -->