Hi @Pawar, Monica,
Unfortunately, we don't have an out-of-the-box way to create 4 levels of links in SharePoint at the moment.
According to the SharePoint documentation, we can create at most 2 levels of links under a link. That means we can create up to 3 levels of links.
Reference: Customize the navigation on your SharePoint site
We are always looking for ways to improve SharePoint, and your feedback and suggestions are very valuable.
We suggest that you can make suggestions on this SharePoint Feedback portal for creating 4 levels of links in SharePoint. Your contribution will be highly appreciated.
Have a nice day!
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