Start with a 40/40/20 macro split based on your daily minimum caloric requirement. Up the calories by 100 per day after the first couple weeks until you find the qty that fits you best. Reduce carbs to shred or up them to gain. I do a 50/30/20 based on 2100 calories daily as im on a cut.
It takes time and practice and most of all experimentation to figure out what diet is best for you. I take in 1.5-2 times my weight in protein as a general rule.