I've been working on my data pack recently and have been experimenting with new features (Sonic screwdrivers) and I was wondering if there was a way to add them in with a data pack/resource pack, I have added every json file that I seem to need for it so at this point I'm not sure what to do. Is there a models folder that has the models for the screwdrivers that I can't seem to find? Also can this be done for new blocks (I.e. new Tardis interior doors). If there is no way I can convert to a full on add-on mod but I want to see what options I have. Any help is appreciated.

right now only way to add sonics is by adding it to the code (unless im missing something)

 What would you mean by that?

Is there a source code type thing I'm missing (where would I find this?), do I need an add-on pack for that?

 You would need to make a java mod to add new sonics, as they are all custom items