Hi there!
I have objects with ‘DontDestroyOnLoad’ script, such as camera, managers etc.
My question: is it possible editing selected scene, press ‘Play’ in the editor and start game from another scene (where I have base objects)?
Sorry for my awesome English and thanks.
No, that is not possible in the editor – don’t destroy on load does not spawn these objects in the scenes, it merelly prevents them from destruction upon loading another scene. For testing purposes just put those objects in the scenes you are testing 
EDIT: You can also add a few buttons or keyboard shortcuts to load the levels you want on runtime. Just compile a script that you’ll throw away at the final build time
Ok. Thank you.