2 solutions to that matter:

1. Standard solution : you should enable the "developer mode" (in Configuration), and browse your mouse on selected fields in Odoo to get more information (name of the field and description if available).

2. Advanced solution : in order to see the total list of fields and their label/description, you should enable the “developer mode” and go in Configuration/Technical/Fields. There, you can “group by” object in order to see the fields available per model in Odoo. What interest us is the “field label” (=name of the field) and the “field help” (=description of the field - if any is available). For convenience reading, you can do an export of the desired fields with these 2 specific fields.


Note there are a lot of fields and depending on the configuration and business flow, the fields can be used and displayed in a different way. Therefore looking directly in the list of fields is not the most efficient, hence the reason why we don't have a specific documentation about them within Odoo.