hey brother, good to see you posting
sounds like you need some sort of stable standard by which to begin planning your diet. i'll tell you what i'd do, but i'm not an authority on nutrition or training. if some of the more experienced members chime in with something different, go with their advice.
i'd start by deciding on a goal weight
, say 200 lbs.
now you can figure out your basic protein needs -- 1 gram per lb. of body weight is a good start, at least. so that's one of your macros figured out: 200 grams of protein
what about carbs and fat? different people suggest different splits. i've seen 40% carbs, 40% fat, 20% protein. i've also seen 33% carbs, 33% fat, 33% protein. and of course there are lots of radical variations depending on your nutrition goals. let's go with the 2nd one: 33%/33%/33%
here is a rough estimate of calories per macronutrient:
1g protein = ~4 calories
1g carbohydrate = ~4 calories
1g fat = ~9 calories
so if 200g protein will be 33% of your total calories, then...
33% protein = ~200g = ~800 calories
33% carbs = ~200g = ~800 calories
33% fat = ~90g = ~800 calories
so you're looking at ~2,400 calories total
. again, i don't guarantee any particular results with this "plan," this is just perhaps an entry point into beginning to plan your diet. i hope you'll set up a diet and/or a training log so that we can check out the specifics of what you're doing!