A family of Microsoft products that enable users to capture, organize, and reuse notes electronically.
Hello 陆行,
We’ve got your concern about merging cells OneNote. Let’s work together to resolve your concern.
In order to merge cells in OneNote, you might need to manually copy the table from Word, perform the merge then copy it back to OneNote page as merging cells in tables in only applicable in Microsoft Word. For your reference, you may check this article: Merge or split cells in a table.
Since the options isn't yet available in OneNote, we would like to have our engineers be aware of the said feature recommendation. I would recommend posting your concern on our OneNote UserVoice as Microsoft continuously strives to improve its products and to provide a better experience to its consumers.
Your entry in the UserVoice will help our support engineers to gather data on how they can improve Outlook and its features and this will also represent other community members who also wanted the same feature suggestion. Our engineers responses may also depend on the upvotes on the current entry.
Should you need further assistance, feel free to post back to Microsoft Community.