Charges from the item equal to the number of helpful spell levels the metamagic feat would increase to your spell. If you need to do go with a Barbarian/Artificer, you may come across Rage interfering with your infusions/magic items. There's no Formal way about this, but you may perhaps question https://aarakocra-wizard58902.idblogz.com/28578544/the-best-side-of-dark-elves-d-d