Multisite Craft 3, different entries on different sites Is it possible to show different entries on different subsites?

Currently I can show different versions of the same entry (e.g. translations), but I want entry 1 to show on site 1, entry 2 on site 1, entry 3 on site 2, etc.

As I have different user accounts for the admin for each site, is it also possible to only show the entries for site 1 in the cms of site 1?

In total I'd like to create around 30 subsites.

Update - site setup

I'm working with only 1 locale. I have one primary (default) site, the rest is in the same group, all on a different base URL and handle.
For future reference, this was fixed in 3.0.0-RC15


  Added the “Propagate entries across all enabled sites?” section setting. If disabled, entries will only be associated with the site they were created on.