Hey!
Welcome to the program fatwhome! I think you will find this forum an invaluable resource in regard to support and inspiration from fellow losers! Katydidnext is right about cooked meat weighing less than raw. If you're going to take your allowance from cooked meat, take away 20 - 30% of what you were allowed. So if you want to tuck into that roast chicken (without skin lol

) and your allowance for that meal is 105g, then take approximatly 80g. I personally prefer to cook all my meat myself, that way it seems like im eating the full amount lol, and not a percentage of what i am allowed!
Good luck on your journey!