Sorry, this is probably dumb, but what does ESL mean?
What Crimsonrider said. In short - a 4 Bard/2 Cleric is, naturaly, the mentioned level in those Classes and Character level 6.
As both Bard and Cleric are Full Casters, the Char's ESL is 6, with the appropriate Spell Slots, i.e. 4/3/3, in spite of not knowing any lvl3 Spells (must upcast to use those slots).
Paladins and Rangers are Half Casters, Eldritch Knights and Arcane Tricksters are Third Casters, while Warlocks are Freaks.
Hence a 5 lvls Cleric and 2 lvls Ranger is ESL 6, i.e. 5 + (1/2+1/2).
https://bg3.wiki/wiki/SpellsNear the bottom of the page, see table.
Quite useful if you lets say want to play a Paladin multiclass that can smite 16 times without long resting;
![[Linked Image from i.imgur.com]](https://i.imgur.com/8KjpcS8.jpg)
That's CHAR level 12, with ESL 11, from Cleric, Bard, Wizard and 2 lvls of Paladin?