Bootstrap 5 Reboot Code blocks are used to put the code inside of <pre> tag, according to official docs we recommend that you avoid using any angle brackets inside of <pre> tags. This is used to remove the default margin of the HTML pre tag element.
BootStrap5 Reboot Code blocks Class: There is no predefined class to do the Reboot Code Blocks.
BootStrap5 Reboot Code blocks Tags: The HTML code tag has to use with the Bootstrap CDN link, it removes the extra space.
Syntax:
<pre>
<code>
...
</code>
</pre>
The below examples illustrate the BootStrap5 Reboot Code blocks:
Example 1: In this example, we will put some C code inside the <pre> and <code> tags without the formatting.
<!DOCTYPE html>
<html>
<head>
<link href=
"https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/css/bootstrap.min.css"
rel="stylesheet" integrity=
"sha384-EVSTQN3/azprG1Anm3QDgpJLIm9Nao0Yz1ztcQTwFspd3yD65VohhpuuCOmLASjC"
crossorigin="anonymous">
</head>
<body class="m-3">
<center>
<h1 class="text-success">
GeeksforGeeks
</h1>
<strong>
BootStrap5 Reboot inline code
</strong>
</center>
<code>
#include>stdio.h>
int main() {
printf("Hello Geeks");
}
</code>
</body>
</html>
Output:

Example 2: In this example, we will put some C code inside of the <pre> & <code> tag with the formatting by putting them in a <pre> tag, and because of the <pre> tag, it removes the color.
<!DOCTYPE html>
<html>
<head>
<link href=
"https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/css/bootstrap.min.css"
rel="stylesheet" integrity=
"sha384-EVSTQN3/azprG1Anm3QDgpJLIm9Nao0Yz1ztcQTwFspd3yD65VohhpuuCOmLASjC"
crossorigin="anonymous">
</head>
<body class="m-3">
<center>
<h1 class="text-success">
GeeksforGeeks
</h1>
<strong>
BootStrap5 Reboot Code blocks
</strong>
</center>
<pre>
<code>
#include<stdio.h>
int main() {
printf("Hello Geeks");
}
</code>
</pre>
</body>
</html>
Output:

Reference: https://getbootstrap.com/docs/5.1/content/reboot/#code-blocks