Manual completion Tracking - New Learner experience

Hi,

We have turned on Manual completion tracking in New Learner Experience on one of our modules (we think we must have done this before we swapped to new learner experience; as now can't find the setting).

So it looks like this to learners. And they have to tick that they have completed it

Three questions:

1. Where is this setting to turn on manual completion tracking within a course. I presume if you marked indivdual pages of content as optional you wouldn't mark as complete? Or would you still be able to mark as complete? Its just flagged as optional?

2. Is there a way to turn this setting on for lots of courses in one go? I.e At the parent org unit ie. Department? Or Course Template?

3. Does this manual compeletion tracking reflect onto the Visual Table of Contents even when on New Learner experience? We still have this on our course home page, as we like to have a course home page to add announcements etc.

We want to test it on one module first with our learners to see what they think, and if they find it useful or just annoying to remember to click the button. And if they like it then we would look to roll out wider.
We have hundreds of courses though so don't want to do it on an indivdual basis and risk missing a course out. And learners being confused why it is there on some of their courses and not on others