New to this

Hi, I'm Brian.
I'm new to this macro thing been counting calories for about 2 years now cause of my eating disorder. Anorexia. But thought I need to get control of my life and heard this was the best app. Would love any help at all. Ano this is stupid but I have no idea how macros are important a generally thought focus on calories and how do I decide what macros a should hit. Currently to skinny to life weights just need to gain weight as this moment in time. I'm a male if use haven't guessed lol. 5ft 11 and weight roughly 8st 7 but that depends on the day cause what I found out in the first few days of recovery is you go on eating binges and I literally ate 3500 calories within an hour and was still hungry but this is supposedly normal. Would love any help or tips and recipes. Thanks guys