I have a sorcerer with 10 dex, which is +0 and 16 cha which is +3
So if I make a dex saving throw, I get +0 as I have no proficiency
If I make a cha saving throw, I get +3 and since I am proficient in charisma I get my proficiency bonus which is +2
The bit I am struggling with is, if I make a performance (cha) check, which I don't have proficiency in, do I get just +3, or do I get +5 because I am proficient in charisma even if I'm not proficient in performance? Or does that only apply to saving throws?
Likewise if I make a persuasion check and I have persuasion proficiency, is it +5 (+3 and +2 prof. bonus because it doesn't stack twice)?