Relatively new player to the game, need advice on specific questions

Hello, I bought this game since I saw it on discount at 3,99 and decided to get it alongside a friend. I also got the Forgotten DLC.

1. Is the community still active?

2. How is the community acting towards newbies?

3. Can the game provide more than 20 hour or so of fun?

4. Why can my friends only play ~7 DLC civs when I can play all of them?

5. Any general advice towards a new player? Looking to play MP as I get better.