Luke 5:32 I came not to call the righteous, but sinners to repentance.
I have not really set out to invite law-abidings but errants.
The word translated as "I am come" primarily means "to start out." It indicates movement, especially its beginning, without indicating a direction toward or away from anything, so it works either as "come" or "go," but it is more like our phrase "being under way."
The term translated as "call" is like our word "call" means both "to summon" and also "to name."
The term translated as "righteous" means "those who observe the laws", "well-balanced," and "meet and fitting." However, when used as a noun referring to a group ("the righteous"), Greek uses the article ("the") just like English does. No article is used here so its form is more like an adjective.
The Greek word translated as "but" denote an exception or simple opposition. "Still" or "however" work well when the word isn't being used as a conjunction, especially when it begins a sentence.
"Sinners" is a Greek word that means "erroneous" or "erring." It also means "of bad character" but with the sense of being a slave or low-born not evil. Only in biblical translations is this term given the sense of wickedness. More about the translation issues regarding "sin" in this article here. Again, when used as a noun ("the sinners"), Greek uses the article ("the") just like English does. No article is used here so its form is more like an adjective.
οὐκ (partic) "Not" is from ou which is the negative adverb for facts and statements, negating both single words and sentences. The other negative adverb, μή applies to will and thought; οὐ denies, μή rejects; οὐ is absolute, μή relative; οὐ objective, μή subjective.
ἐλήλυθα (verb 1st sg perf ind act) "Come" is from erchomai, which means "to start," "to set out", "to come", "to go," and any kind of motion. It means both "to go" on a journey and "to arrive" at a place.
δικαίους (adj pl masc/fem acc) "Righteous" is from dikaios which means "observant of rules", "observant of customs", "well-ordered", "civilized," and "observant of duty." Later it means "well-balanced", "impartial," and "just."