Google Forms – two required questions – accept with at least one of them

I collect links to historical records describing persons falling into certain categories (e.g. secret Protestant or vampire/witch case). User specifies the Category with a checkbox answer (multiple options possible).

I want to add more options, describing professions. But now the checkbox list would be too long.

I want to do either:

1. Add a separate question Profession. One of the the two questions Profession and/or Category must be filled in (required question) or
2. Format the Category question so that the options are organized into sections or the checkboxes appear in multiple columns.

I do not want to add additional form page.