Negative feelings when building my business

I have done my coach certification and the plan is to set up a coaching business. I am still part-time employed, but I am not taking action towards the business. Whilst it was always my wish to have a business, earn a certain amount and live location independent, I have lost the appetite for building the business. Many times thoughts are coming up like: What’s the point, this will never work, why are you even doing this and then I stop working on it and engage in self-pity. I am also afraid that I can’t find clients and use every opportunity to beat myself up. I have watched my thoughts for a while, and now I am working on intentional models and feeling the discomfort. Every time I come to this point, I tell myself that this is normal and I should continue, but I feel now so bad that I am questioning if I even want the business.
The same thing happens with food. I have been told by the doctor that I should be loosing some weight in order to get a lower blood pressure and cholesterol, but since I was told this, I eat more shit than ever. Again, I am having similar thoughts like, this will never work, what’s the point etc. Also, I was watching this for a while and then went to intentional models, but the corresponding feeling is not coming up for me.
Going through this all, I even doubt now whether I am a coach or not.
I would love some guidance on how to approach this.