Can one tell me how to make three menu navigation bar. And with code

Answer 1

https://getbootstrap.com/docs/4.0/components/navbar/

Here u will get the basic source code.
1) Include bootstrap CDN in head of ur document.
2) Add the navbar code in ur body of ur document. And see the result while reducing the width of the chrome tab.
You will be getting that handburger symbol while the width is getting low as same as phone width.

Answer 2

By bootstrapping your code

Here's example of code:
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<div class="container-fluid">
<a class="navbar-brand" href="#">Navbar</a>
<button
class="navbar-toggler"
type="button"
data-mdb-toggle="collapse"
data-mdb-target="#navbarNavAltMarkup"
aria-controls="navbarNavAltMarkup"
aria-expanded="false"
aria-label="Toggle navigation"
>
<i class="fas fa-bars"></i>
</button>
<div class="collapse navbar-collapse" id="navbarNavAltMarkup">
<div class="navbar-nav">
<a class="nav-link active" aria-current="page" href="#">Home</a>
<a class="nav-link" href="#">Features</a>
<a class="nav-link" href="#">Pricing</a>
<a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true"
>Disabled</a
>
</div>
</div>
</div>
</nav>