Order comments for order or item

Hi,

I wish to add a textarea for each order to add some order comments (like ‘deliver in 2 boxes’, ‘will pick up at 8.30 pm’ etc). Is there a way to do that?

Which file should edit to add this? Any code snippet you can help with?

Thanks.
Ravi.

https://www.ads-software.com/plugins/wppizza/