"Known to" means that someone or something is known to a specific group: i.e. This snake is the deadliest one known to man! **Here, the snake is one of the deadliest known to mankind (specific group) "Known for" means that someone/something is recognized for some special trait or quality: i.e. The chef is known for his delicious lobster. **The chef is recognized by other people for his lobster (it is very delicious, which makes it a special feature)

Your sentence would not be right because "known for" always has to be followed by a description. "He is known for playing the piano." "Brad Pitt is known for his acting." Does that help?

be known for something means that you're known by a lot of people (famous in other words) because of that something. So "He is know for the singer in the world" is incorrect but: "He is known for being a singer" "He is known for signing" "He is known for his songs" are all correct