I think Healer is one of the best possible choices for a starter drama, especially if you like a good mix of romance and action. My friend began with My Love From The Star and it got her into the drama world~ pretty successfully, so maybe that as well? Tbh, the ones I started on (Playful Kiss, Boys Over Flowers) I probably wouldn't touch now. If you really want to see the ones that started it all for most drama watchers, the Endless Love series (Autumn in my Heart, Winter Sonata, etc), Boys Over Flowers, Stairway to Heaven, My Lovely Sam Soon, Coffee Prince, Goong, Dong Yi, The Reply series (Reply 1997, 1994, 1988), DOTS, Secret Garden, etc are musts. There'll likely be a genre that stands out for you and you'll delve further into it -- aka if you end up liking Healer, I'd rec anything from Empress Ki (when you feel ready for ~longer/historical shows) to Signal (a crime/action masterpiece without the romance aspect). Since you started from anime, maybe look into shows with the same ~feeling as liveactions (for this, I'd recommend Hong Sisters dramas, Sassy GoGo, R1997, Moonlight Drawn By Flowers...) Maybe take a look at my list of favourites (those I'd rec to pretty much anyone) or the lists of anyone who has responded, everyone has different taste, but you'll find a lot of the same stuff being ranked highest.