Is There a Male Protagonist Who Knows Everything, but Keeps a Low Profile and Helps Solve Problems?

Want to watch something like "Killing chickens and cooking at the beginning, do you call this eight years old?" Book. The male protagonist keeps a low profile in his life. He is an ordinary person who is handsome in the eyes of others. He is usually unknown and doesn't like to stand out, but when everyone can't solve the problem, he can talk about it and solve it effortlessly.