Can two objects be the same (on a molecular standpoint)? Is it possible to create two objects that are the same on the molecular level?
By two objects, I mean two different objects that have the same label.
For example, can you create two different breads that have the same molecular structure? How do we know that they don't?
Are all iPhones 8 structured molecularly the same?
Can two cars (made by the same brand, and called the same car) be molecularly the same?
What about drinks?
Let's say someone orders a sprite. Are any other sprites the same in regards to the molecular structure?
 A: Practically, obviously no, since there are too many parts involved (like $10^{23}$) that cannot be controlled in all of their properties. That means that many molecules will be in a different microscopic state even if seen together, they look the same on a larger scale.
By the way, the order of magnitude of possible states that all look the same to you - think counting the number of zeros after a one, like 100, 1000 etc. possible states - is called entropy. And having a temperature means that random molecular motion will decrease your knowledge about one object and at the same time the similarity between two objects on the microscopic level. So you always have increasing entropy and ever less information about your objects which prevents you from stating that they are "absolutely the same".
But also theoretically, no, because being in another location in space is being different - it is another state quantum-mechanically, even if it requires the same energy etc.
No two matter particles (fermions) can be exactly in the same state according to the Pauli Exclusion Principle.
But you can cheat: If you are not interested in some of the microscopic state, you can just ignore some entropy (missing information), and declare: "These two objects are the same as far as I am concerned". That is what we are doing all the time for the sake of abstraction.
Or more philosophically: Whatever you say about anything - it is just a model in your mind. If you conceive the two glasses of Sprite to be identical for the purpose of drinking with a friend, they are the same - or even more coarse: You both just drink "some Sprite" - so there are not even two distinct objects in that "theory". But once you include individual bubbles, molecules, quarks etc. in your mental model because you are performing experiments with them, at some stage, the two glasses will turn out to be different. That is just because you get more and more possibilities for the states they can be in, and random influences like thermal motion will act differently on the two objects.
