Hi @TankAdmin,
You could create an Excel file before you create the Flow, the Excel table should contain columns to hold these pieces of information from Planner, such as Title, StartDate, DueDate, Description, etc.
Then create a Recurrence trigger runs every one week, then list tasks and create an Apply to each action to loop through each task, if the task created time is greater than or equals to 7 days ago, add this task into the Excel table:

Then, you could send this Excel file as an attachment in an Email.
Best Regards,
Community Support Team _ Lin Tu
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.