Please go to the following section of the forum and start your own thread. 
then come back here and delete your post in this thread. (Make sure you say what country you are in, as options do vary somewhat.)
https://community.smartthings.com/c/projects-stories
People will be glad to help you there.
So I ordered zooz zen21 on off switch that would be my very first device. As I mention at the beginning oh this thread I have smartthings v2 still in box. Anything I should now or is hub setup straight foward?
Well, my V2 hub setup (about a year ago) was very straightforward. Nothing is ever guaranteed, though.