This particular inquiry mirrors previous questions found on Stack Overflow, such as this one and that one. However, the convoluted Bootstrap grid structure you've employed is causing difficulty in achieving the desired height.
If you follow the advice provided in your other posts to simplify the markup, then resolving the height issue becomes straightforward by utilizing the flexbox grow and shrink utilities, as outlined in the Bootstrap documentation...
"Use .flex-grow-* utilities to toggle a flex item’s ability to expand and
occupy available space."
Implementing classes like vh-100
, flex-grow-0
, flex-grow-1
, flex-column
, etc...
<div class="container-fluid d-flex flex-column vh-100">
<nav class="navbar navbar-expand-lg navbar-light bg-light">
...
</nav>
<div class="row flex-grow-1">
<div class="col-md-4 bg-warning">
<!-- content for the left side -->
</div>
<div class="col-md-8 bg-primary d-flex flex-column flex-grow-1">
<div class="row flex-column flex-fill">
<div class="col bg-success flex-grow-0">
<div class="row">
<!-- ideally should occupy full width but currently an unwanted scrollbar appears due to this section... -->
</div>
</div>
<div class="col bg-info flex-fill">
<!-- Intended for central placement and occupying full screen (resembling a chat interface)--> Message </div>
<!-- positioned at the bottom of the screen similar to conventional chat interfaces-->
<div class="col bg-success flex-grow-0"> Text Input and Button </div>
</div>
</div>
</div>
</div>
Check out this demonstration on Codeply