What initially drew me to David Hume was a quote from his discussions of miracles in "An Enquiry Concerning Human Understanding" (name of chapter is "Of Miracles").

That said, I began with "A Treatise of Human Nature" around the age of 17, translated to my native language (his works are not an easy read in English, IMO), due to my interest in both philosophy and psychology.

If you haven't read them yet, I would certainly recommend them. I would recommend the latter I mentioned even if you are not interested in psychology (but may be interested in epistemology, philosophy of mind, and/or ethics), as he gets into detail about his "impressions" vs "ideas".

Additionally, he is famously known for his "problem of induction" which you may already know.