Isekai manga about a guy who trains with a guild master, joins a church and becomes a healer, and then goes floor by floor up a dungeon

Question

It's about a guy who goes into an adventurers guild and trains with the guild master, and then joins a church and becomes a healer. He drinks stuff that they call really nasty and it smells insanely bad, then he trains and goes floor by floor up a dungeon with undead monsters.

Answer 1

I believe this is The Great Cleric, also known as Seija Musou: Salaryman, Isekai de Ikinokoru Tame ni Ayumu Michi.

The main character dies and is reborn in another world as a healer. He finds a town, and is taken to the healers' guild. He joins and gets a crash course in healing magic. After learning the basic healing spell, he goes to the adventurer's guild. He trains there, drinking a nasty drink that is supposed to help with ability growth, for a year.

Later, after a dispute with another cleric, he is sent to the main temple. There he spends his time cleansing a dungeon filled with undead monsters.

Answer 2

This is The Great Cleric

One man’s story of turning blood, sweat, and tears into a successful living—literally! After his untimely death as the hardest-working salary man in Japan, Luciel is reincarnated into the magical fantasy world Galdardia. Always the man with a plan, he recreates himself to be a healer, and sets about making his way in the world.

The disgusting drink is referred to as Substance X and appears early on. It makes you stronger, but is so disgusting no one (except Luciel) is willing to touch the stuff.

The story arc with the dungeon filled with undead takes place around 20 chapters in.