Levelling Up In An Exclusive Dungeon is a Manga/Manhwa/Manhua in english language, Action series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.cc fastest updating comic site. The Summary is

Kang Jin-hyeok, a D-rank hunter for years. His days were spent barely scraping by with part-time jobs, unable to level up due to the hunting grounds being controlled by major guilds.

One day, a dungeon appears in his room.

“This is… a dungeon?”

With the dungeon now in his possession, Jinhyuk begins to successfully hunt, level up, and gradually grow stronger…

“Just wait and see, you major guild scumbags who looked down on me!

I will become strong, with this dungeon!”

Level Up Through Dungeon Exclusivity | Leveling up by Monopolizing the Dungeon | 던전 독점으로 레벨업