We are migrating from Classic to Lightning Experience. We are first migrating on our sandbox, then we deploy the changes to production, but once we entirely migrate an object to production, let's say Delivery__c object, we only want to show that object in Lightning Experience, and the rest of objects in Classic Experience. Is this possible to accomplish? I checked the entire trail head for Make the Move to Lightning Experience, but I did not find any article related.
Not really, the point of lightning is for your whole interface to change. You could create an app with only that object available as a tab, but all the other objects will still be available through the app launcher, or from the add tabs section. I honestly found it a lot easier through setup everything from the preview mode, saved me a lot of time and worked better than going back and forth on Sandboxes.