Always Second but Actually Invincible 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

Cleo Farshid has been disowned from his noble family due to his inability to be number one in anything at the Royal Academy. Cleo decides to escape his stuffy life and live more freely, taking advantage of his skills to become an adventurer. Neither he or his father have realized how amazing it is to be ranked as second in everything at a school where the most talented compete. "I'm just an average person. I'm not an expert in anything." That sentiment kicks off an unmatched tale about a boy who is the strongest specifically because he's always second!