I was wondering how can i modify the sort by , i mean when i nav through collections , it appears , sort by title , and add date , how can i modifiy or add , a sort by id 
can’t find it how
Are you using Omeka Classic or Omeka S? “Collections” is a term from Classic.
Added date and ID are generally going to give you the same sort order. Or do you mean you want to sort by the Identifier metadata field?
sorry , i understood how it works , my bad , my really question is , how can i modifiy the sort by , for example , later on when i click on Added date , i want that it shows me just the last 2 added , that just 2 registers appear , not all the registers