I was just like you did not know what to eat or nothing. but mine was because I wanted to abide by the 'healthy way to gain weight rule'. I had to do everything perfect and I searched everywhere for a guideline, a clue anything to show me what so called 'perfect' was.. but everywhere told a different story, different set of rules.. so I decided to do it my way the way I could say yeah, I can manage that.
You should sit down with some paper and a pen and write down the foods you normally eat, but also the foods you are willing to try. Then using your list make up a plan of what you would eat each day. Starting from breakfast, then snack, dinner, snack, tea and if you could manage it another snack before bedtime. eating before bedtime sure helped me go from 5 stone to where I am now.
I wish you luck with your recovery and hope you find a way which you can achieve it.
I am always here if you need support