Hello Nikhila,
Thank you for contacting the Microsoft community. I'd like to let you know this is a peer-to-peer support forum meaning I'm just fellow regular MS forum users like you who are trying to help other MS forum users with their issues. I'm a Non-Microsoft Staff I don't have access to your account, nor I'm authorized to do so.
Export to Excel:
In the Planner web app, click the “…” at the top of the screen, then select “Export plan to Excel.”
Your entire plan will automatically download as an Excel file to your machine.
The downloaded file includes details like assigned tasks, start and due dates, descriptions, labels, and more.
You can look up the answer given by Monika Dragulski via this link https://techcommunity.microsoft.com/t5/planner-blog/planner-export-your-entire-plan-to-excel-for-powerful-analysis/ba-p/717431
Regards
Ruth