First click on the stage "Layout" and then select a page.

Please drag and drop the product items to a specific content block from your template.

There's an option to reshape the item size over several content blocks. To do this, move your cursor on the image, then an arrow icon will appear in the down right corner of the image. You could use this icon to reshape the size of the item.

If you want to delete an item, move your cursor on the image. Then a delete icon will appear in the top right corner of the image. Click on this icon.

You also can place a note on the page. Click in the box of the template where you want to place the note and a pop-up screen will appear.

Choose a color for the note box and give up the description for the note.
Then click on "Save".

If you are ready with the lay-out you can set the page to the next stage: "To Design".
Then the Indesign-file is being generated.