Children have limited ability to manage their emotions, so they need caring adults to help them "co-regulate," especially when they're very agitated or upset.
To develop the self-belief, "I am capable," kids need an optimal amount of challenge, through which they develop skills, and learn mental habits like grit and perseverance.
To a very large extent, how well kids do depends upon how well connected to their caregivers they are.
You may wish many things for your child in life, but underpinning most of them is a secure a resilient sense of self. As a parent, how do you develop this sense of self?