Just One (best party game ever designed) Splendor (intro to "engine builder" games) Carcassonne (intro to tile laying games) Sushi Go (intro to "drafting" games) Scout (intro to climbing/shedding card games)

All of these are very inexpensive and rules light and very approachable for beginners.

I liked Colony which is vaguely like Splendor, but it's not cheap. And I liked Splendor.