Give us some more information =]
To create new items, you need to create a minimum of the following
PrimalItem<type>_name
If you want it craftable
EngramEntry_<Name>
If it has a 3d model
<Item Core Blueprint>
If it has Ammo
PrimalItemAmmo_<Name>
If it is a structure
PrimalItemStructure_<Name>
PrimalItemInventoryBP_<Name>