Google Sheet Link

When you finished creating your sheet, click a "Share" button on top right corner.

 

Click "Get shareable link" on top right corner of the modal.

 

 

You will see a link to your sheet. Make sure it has the "Anyone with the link can view" option selected. Copy the link to add-on's form and you will see your data in chart. Every time you update a sheet, it will be automatically updated in your block.