You can’t create multiple choice grids with Airtable’s forms, but you could create a single-select dropdown menu for each ethnicity.
If you really want a multiple choice grid, you would need to use JotForm to do this. This is a native built-in feature of JotForm, and it’s called an “input table”.
Then, you could send your information from JotForm to Airtable using JotForm’s native Airtable integration, or if you need a more advanced integration, you could turn to an integration tool like Make.com.
You can probably figure all of this out on your own, but if you need help from an Airtable/Make consultant, feel free to contact me through my website at scottworld.com.