BuddyPress.org

@Haraldo88

1. Yes, you get that out of the box.
2. There are a couple ways to make this happen. One is a plugin called BP Album (or BP Media): http://code.google.com/p/buddypress-media/ Another is a simple forum attachment plugin, which is a bit outdated and not easy to set up on all systems, but might be worth a look: https://wordpress.org/extend/plugins/forum-attachments-for-buddypress/
3. BP Media is your best bet for that.

Good luck with BuddyPress!