(This thread isn’t for new users of Picard - it’s for people who have got experience that might help new users.)
What questions would you suggest a new user of Picard ask?
(Yes, they’re not all the same skill level - just share the questions that you wish you’d asked if that works better for you.)
How many songs can I add to Picard?
How many songs will Picard detect automatically?
What’s the difference between the songs on the left and the right side of Picard?
What’s the meaning of the different colors on the right side of Picard?
What’s the difference between “Lookup”, “Scan”, “Lookup in Browser” buttons?
What are Clusters?
What’s the difference between a plug-in and a script?
Where can I find example scripts?
How do I get Picard to name my files like [specify format]?
What happens when I click the Remove button?
How can I get / select cover art?
What do I do if Picard can’t find my album / songs when I do a lookup?
Ideally they shouldn’t ask anything, Picard’s interface should just be so intuitive that everything is obvious! 
That’s not going to happen anytime soon though. Interesting topic. 
@Freso
I hope that you will also make editing MusicBrainz intuitively obvious as well. But why not do that this month? ROFL
A couple of questions that I brought to Picard many years ago. And a few I should have had answers to before starting.
Why would I tag my music?
What is “tagging”?
Should I back-up my music collection?
How much disk space do I need to use Picard?
Why do the “new tags” not stay in the files?