I have looked online for some results, but did not figure out how I could get an item with a custom model data, let's say 1.
/give @a paper[custom_model_data={id:2}]
/give @a paper[custom_model_data={id:2}]
This is what I tried, but once I change to other ids, the items stack on each other, indicating that the custom model data did not register. Could someone help me?