When we say we're seeking for help from God. We look up to him. Is this correct ?
The word to be careful of here is "up". To look up to X is an idiom meaning "to have respect or admiration for X," and implies that X is seen as something of a role model.
Omitting the word "up", to look to X is an idiom with the meaning you want. It means to rely on X for help. Usually with this phrase you would also add what you are hoping for. For example, "I looked to my parents for support", or "He looked to his friends for help."