do domain spells use spell slots
Create Spell Slot | Baldurs Gate 3 Wiki
There are six levels of spells and each spell can only be cast using a spell slot of an appropriate level. So, if a character wanted to use Fireball, a level 3 spell, they'd need to unlock a level 3 spell slot to use it.
Where to find Memory Stones in Elden Ring | Rock Paper Shotgun
In this guide, we cover every Memory Stone location in Elden Ring that we've found so far, allowing you to gain more spell slots and use more spells in combat.
Baldur's Gate 3: Best Spells For Crowd Control - Game Rant
Also unlike D&D 3.5, you do not prepare spells at a given spell slot. Rather, you prepare which spells you know, and 'spontaneously' decide when to cast them.