
Hi @Ahmed Hablas ,
Here are steps:
1.Go to the Microsoft 365 Admin center
2.From the Microsoft 365 Admin center, choose SharePoint from the Admin centers section in the left bar
3.From the SharePoint Admin center, click the Active sites option under the Sites section on the left
4.Sort the URL column in alphabetical order
5.The current root site will appear first in that list. Select the root site and click on the more options ellipses at the top.
6.Choose Replace site, and enter the new root site URL in the URL of the site you want to use
Reference: https://blog.mydock365.com/how-to-change-home-site-in-sharepoint-online
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