Make Navbar Sticky for Better User Experience

[ShaikHafiza]

The current navbar is not sticky, meaning it does not remain visible as users scroll down the page. For improved navigation and user experience, especially on pages with long content, the navbar should remain fixed at the top of the page while scrolling.
Making the navbar sticky will keep these important links easily accessible at all times while scrolling through the website.

@Tejashri-Taral Please, assign me this issue
I will do this in very short time.

[github-actions]

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