Dear Engineer Bilal,
Thanks for your question. Yes of course you can add more than one project in the database. It is the main purpose of using Power Bi actually. You can update each project and use our Excel Macro to do so then paste the results to the database and start adding a new project and so on. The data should not be overlapping if you add one project per time.
In order to attach files to your post, please follow the steps in this post: https://planningengineer.net/forums/topic/how-to-attach-xer-or-power-bi-file/
Please let me know if you have any further clarifications.