Explanation:

- Option 1: Depend on oneself

- This is the correct meaning of the idiom. "To paddle one's own canoe" means to be independent and self-reliant. It implies managing one's own affairs or making decisions autonomously.

- Option 2: To take rest

- This option is not related to the idiom. It suggests relaxation, which is unrelated to the concept of independence.

- Option 3: To exercise hard

- This option is incorrect. The idiom is not about physical effort or exercise but rather about self-dependence and handling one’s own matters.

- Option 4: To act in a childish way

- This is also incorrect. Childish behavior generally implies immaturity, which contrasts with the self-reliance the idiom describes.