Is it possible to customise field type or include validation in a field type?

Is it possible to customise field type? Let’s say text field, I need to make sure the user input is a valid Bible chapter or verse. I intend to use chapter-and-verse but not sure where to make it happen.

Also how can I create new field type using strapi?

At the moment we don’t support custom fields (yet) and plan to in the near future but there are some pre-reqs required to do so.

As for the validation, is this only within the Admin panel, REST, GraphQL, or all of them?

Thank for the response
I would like to include validation within the admin panel

You can create a Local Plugin for your case and add a custom field to it.

Read: Creating a new Field in the administration panel
Watch: Video

You can add the validation part there, to the onChange handler.

Thanks. Would check it out