My fitness journey didn’t have a clear “start point” like a lot of people’s do. I started weight training when I was 18. Now I’m 31 :)
I’ve been lifting seriously though for around 2 years. I only really saw results, though, when I trained and ate somewhat consistently for 8 months. And by results I mean, noticed my butt got substantially bigger!
Your mileage may vary. It all depends on how you train, how HARD you train, how CONSISTENTLY you train, how you eat, and how CONSISTENTLY you eat, and what results you want.
Whatever gives you enough protein without too many calories! I aim for at least 100g of protein per day, and an average of 1600 calories per day. Eating lots of green and veggies never hurt anyone.