Tables should be designed so that a screen reader can easily navigate and interpret them. In Microsoft Word and PowerPoint, column and row headers can be added to tables to help describe the data and provide structure to the table.
Please keep in mind that tables should never be used for organizational purposes in documents. Only use tables to display data or show relationships, and keep them as simple as possible. If you have a complex table, consider breaking it into multiple smaller tables, each with its own title. If this is not possible, be sure to add alternative text to the table for additional explanation for someone using a screen reader.
How do I add column and row headers to a table in Microsoft 365?