The materials of enchanting are Essences and Components. Essences come in three different types: Arcane, Primal, and Divine - as well as five rarities: common, uncommon, rare, very rare, and legendary. What an Essence is can vary greatly, as they are things of innate magic that is used to power the Enchanter's creations. They could be organs of magical monsters (such as the heart of a dragon, which would be a rare primal essence), or they can be synthesized from magical reagents into a magical compound. Components are a broad category of items ranging from the base item you are enchanting to any extraneous bits needed to be added. One unique component that is present in many enchantments is a Spell Scroll of certain types of spells that form the basis of the sort of magic the item has.
A crafter that is capable of casting magic can replace the spell scroll in an enchantment with the ability to cast that spell, but when doing so they must cast that spell for each crafting check they make on that item. This is an exhausting process, draining their magic far more deeply than normal casting, and confers a level of exhaustion each time this technique is used to replace a crafting check. If a magic item requires multiple scrolls, only one of them can be replaced in this way, though if an additional spell caster that can cast the necessary spell can assist you, they can replace a second scroll, though suffering the same penalty.
This mechanic is intentionally quite difficult to use - even for casters that are capable of casting the spell. The typical process would be to make the scroll first to formalize their thoughts and process, laying down the patterns and templates for the magic item. It also removes a very costly gate in the process, so should not be easily bypassed.