Hi @evargas ,
Here are the steps you need to follow for your flow:
1. Create a folder in SharePoint or OneDrive document library.
2. Make sure you have the excel or csv file containing data to create the table.
2. Create "Automated Flow" with Trigger Template "SharePoint - When a file is created in a Folder".
3. Read the content of the uploaded Excel File or CSV file.
4. You can update the Planner task directly. Or if you need to write those data to Dataverse - Table. You need to create a Dataverse table.
Refer this link to know how to read the excel file contents: https://powerusers.microsoft.com/t5/Power-Apps-Community-Blog/Power-Automate-Flow-Sending-emails-to-list-of-people-in-the/ba-p/1189517
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