1) Just having the expansion means you are now earning exp again towards 60. All MSQ give exp and you can still do dungeons and fates to get some too. Check your journal to see where you left off. Also the 2 is blacked out in Duty Finder because those are the HW duties that you haven't unlocked yet.

2) Get someone to craft you stuff, or earn poetics to get Ironworks gear. You can still do Zodiac but it's not worth it except glamour.

3) You have to complete all of ARR MSQs and reach Heavensward before you can unlock any of those