Magic Initiate: Sorcerer is a Passive Feature provided by the Feat of the same name. It grants you spells and cantrips from that particular class.
Description
You learn 2 cantrips and a Level 1 spell from the Sorcerer spell list. You can cast the Level 1 spell once per Long Rest. Your Spellcasting Modifier for all 3 spells is 
Charisma.
How to learn
Granted by feats: Magic Initiate: Sorcerer (Feat)