In Elden Ring, there are two types of spells to use: scaling off of different stats and offering various elemental attacks. Incantations scale off of faith and use lighting, holy, and fire damage on your enemies, along with many buffs and healing abilities to benefit yourself and your allies in combat.
Sorceries focus more on ice, gravity, and a few fire and magical attacks. Sorceries are great for glass cannon builds and can do significant damage, scaling off your Intelligence. All types of spells require FP to cast, requiring a good balance in levels to ensure you have the FP to cast the spells you are powering up. Increasing your Mind stat will increase your overall FP and occasionally upgrade the number of spells you can memorize simultaneously. Memorized spells can be switched out at sites of grace.
Incantations
Incantations vary greatly in use and can be used for both offensive spells along with many buffs or healing spells. To use an incantation, you will need enough Faith to memorize the spell and enough FP each time you cast it. Memorizing spells equips them in your hot bar slots and allows you to cycle through them as you play. Equipping a hand seal and using it in either hand will have your character casting the selected incantation. Leveling up your Faith more will increase the damage done or the amount of healing done from a spell.
Many incantations deal high amounts of damage, while others alter and boost the damage output of your main weapon. Other incantations can buff multiple stats for a short time or heal yourself and nearby allies. There are also numerous dragon incantations, which summon an aspect of a dragon and use it to cast a powerful attack. Most of these dragon incantations also require Arcane to memorize along with Faith.
Sorceries
Sorceries are more damage-oriented spells, requiring Intelligence to memorize and requiring staff to cast. The staff can be equipped in either hand and cast spells that range from glintstone magic to throwing rocks with gravity magic and even a few blood-oriented spells that cause bleed. There are only a few spells that also scale off Arcane, helping you focus purely on Intelligence to maximize your damage with a few points in Mind to have the FP cast your spells.
When using a staff, it will cast your currently equipped memorized spell, which can be cycled through in combat if you have multiple spells memorized. With Sorceries mainly focusing on damaged-based spells, there are many to choose from depending on your situation or the enemy you are fighting. It's easy to switch out spells at a site of grace, allowing you to easily counter whatever enemies you find yourself up against.