Numbers doesn't have the feature, but you can set up to 5 rows/columns as header.
The header rows/columns will try to stay on screen while scrolling vertical or horizontal if "freeze header rows/columns" is checked for the table.
Check below in Table menu while the target table is selected.
- Header Rows — specifies number of header rows.
- Freeze Header Rows — Header rows tries to stay on screen if checked.
- Header Columns — specifies number of header columns.
- Freeze Header Columns — Header columns tries to stay on screen if checked.
They are also available in the [table] tab of Inspector pane (sidebar) for Format.
Refer "Add, remove, or freeze header rows and columns" section in Numbers Help for more information.
https://help.apple.com/numbers/mac/4.1/index.html#/tan504013a74