Here are my two cents

1. Abstain from cheap dopamine. This includes alcohol, weed, cigarettes, Netflix, social media, etc.
2. Build a healthy routine including sleeping and waking up early, walking daily in the sun, working out, and eating healthy. Lastly, I recommend journaling daily before bed, jotting down one win of the day, one point of gratitude, and one point of frustration.
3. Pray and get into practicing your religion. You'll find peace in that regardless of your beliefs.
4. Acceptance. Learn to accept your current situation and build from there.

You'll be rock solid in no time if you manage to do the above.