Hi @Kent1,
That’s not a dumb question because what you’re asking is definitely not obvious in Open edX.
The answer depends on the scope of the new field. Is it one field (and one value) per course? (If you want it per unit or per component or something, it gets even more tricky).
If the scope is per-course, the easiest way that doesn’t require modifying the platform is to use “Custom Course Settings” as described in this thread: Enabling Custom Course Settings
That is essentially one field per course that can hold whatever custom data you’d like. However, it requires that the data is in JSON format which may be inconvenient for your course authors to use.
Another approach is to modify the platform to add additional fields to CourseFields, in which case there will be a nicer UI for inputting them on the “Advanced Settings” page of each course in Studio. However, we generally advise against this sort of platform modification as you’ll have to maintain it across all future platform releases.