Candlekeep Sage is a common Legendary Enchantment — Background card from Commander Legends: Battle for Baldur's Gate (CLB), collector number 60. Current market price: $0.30 (foil $0.38), TCGplayer market prices via Scryfall.
Commander creatures you own have "When this creature enters or leaves the battlefield, draw a card."
All Commander Legends: Battle for Baldur's Gate cards and prices