How to display fields on the checkout page for products?

Question

WordPress

There are 2 products on the site. For the checkout page for product 1, you need to display a field with question 1. For product 2, you need to display a field with question 2. I tried plugins - everywhere there are nuances. I came to the conclusion that specifically here it is better to do without plugins. Google doesn't find what I need. How to implement?