SOS Encounter: Resolution Cave (15%), Diglett’s Tunnel (15%, Only in Ultra Sun & Ultra Moon), Memorial Hill (15%, Only in Ultra Sun & Ultra Moon) + 4 more
Walk: Resolution Cave (70%), Thrifty Megamart (40%), Lush Jungle (39%, Only in Ultra Sun & Ultra Moon) + 2 more
Surf: Vast Poni Canyon (80%)
Its base catch rate is 90 out of 255 (higher is easier); the catch rate calculator works out your odds with each ball. For the look, the best colour match is Great Ball or Moon Ball.
Evolution: Zubat → Golbat (Level 22) → Crobat.
Golbat in every game · Pokémon Sun, Moon, Ultra Sun & Ultra Moon interactive map (Alola)