Acquiring Discipline does not happen overnight. The first step is to recognise you need a change in your life. I think it takes time and there will still be “bad” days, however eventually you will notice a difference. I have struggled in many areas of my life and I’m realising its a process to change. Nothing can change overnight. With regards to your diet try by cutting out something and as you get into it cut out more and more foods that are unhealthy for you. Try not condemn yourself. All the best and God Bless.