The first thing I should mention is that there are distinct procedures for inserting text and photo notes. Add a text comment to a cell to start mini crossword with the simpler of the two options.

If you wish to comment on a cell, choose it.
The New Comment icon is located in the Comments section of the REVIEWtab.
A comment can be added to an Excel Note by selecting New Comment from the Comments group on the REVIEW tab. Shift + F2 on the keyboard or right-clicking on the cell and selecting Insert Comment from the menu list are other options you have for completing this task.

• Comments in Excel are essentially notes that may be entered into any cell. It can be used to keep track of reminders, make notes for others, and cross-reference other workbooks. Note that the Show Ink option in the Comments toolbar in recent versions of Office is only applicable for tablet PCs.
• Cells can have comments added to them. An indicator shows in the corner of a cell when it has a comment. The comment shows when you move your cursor over the cell.
• Right-click the cell and select New Comment from the menu that appears.
• Put your thoughts in the box below. If you @mention someone in a comment, they will receive an email notification of the comment.
• Press Ctrl+Enter (or click the Post button).
• If others have something to say, they can right-click the cell and select Reply to Comment from the drop-down menu.
• Rest your mouse over the cell if you need to update a threaded comment. After that, place your cursor over the comment text and select Edit.
• To delete a threaded comment, right-click the cell and select Delete Comment from the menu.
• When a comment thread is finished, you may designate it as Resolved by hovering your cursor over the cell and clicking... > Resolve thread. The remark will remain available, but it will not be able to be edited till it is reopened. Comments can be resolved or reopened by anyone with write access to a workbook.
  

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