I can’t go to my cubes because they disappear like my camera what I see now in scene window is too big.
I want to edit and do more cubes but I can’t with this.
select object and click F while being focused in Scene View
Aaaaaanndd… I just saw comments explaining it to you. 
Basically the thing is, that you have clicked F somewhere, and it changed near clip plane of scene camera. You just need to reset it 
Have you tried to select one of your cube and press the F to focus it?