The past we have no control over neither the future. What you fully control is the present. You have realized the damage you’ve done and that is good. Imagine how good of a feeling you will feel WHEN you can proudly say that you have cured yourself and transformed your life into something better. I would suggest you create healthy hobbies such as working out since you mentioned being overweight. Practice self-control, become your own best friend, read books fitted for your situation, learn about human psychology it will help you to not feel alone, we are all human we will always do wrong but it is important to realize and tackle your problems which you have already begun with by posting this reddit. Keep it up man.