How does UEFA nations league work?

Related questions

1. How often is the Euro Cup?
2. When can I buy tickets for Euro 2020?
3. Where is Euro 2020 hosted?
4. Will England still play in Euro 2020?
5. Where will UEFA 2020 be held?
6. Who will host the World Cup in 2030?
7. Where will the 2020 and 2024 Olympics be held?
8. How many teams qualify from each group for Euro 2020?
9. Can you qualify for Euro 2020 from nations League?
10. How does Euro qualifying work?

Tags

1. #league
2. #simple
3. #place
4. #group
5. #earns
6. #tournament
7. #finals
8. #winner
9. #groups
10. #nations
11. #their
12. #while
13. #teams
14. #bottom
15. #relegated
16. #placed
17. #consisting