How do i join a Community (Away from Steemit for a long time due to work)

I was a steemian for a long time since 2017 posted for 2 years actively but took a break for a year or so because of work.
I am noticing that lots have changed from the last time I was actively posting.
My posts in the past mainly focused on photography and travel and some challenges I found here and there.
I just need your help so that I can actively post again and reach a proper audience following new guidelines.

First, I want to know how can I join some communities, that are proper for me i.e photography, travel and maybe some popular topics to write about.
Secondly, I need some tips on the approach I might take to write blogs and posts that will follow the proper guidelines.

So I will be very grateful if any active steemians will share their knowledge in comments and suggest some communities and how to join them in the comments, thank you all :)