O hes only a little baby! And how adorable!!! I think I see a baby beardie in my not too distant future lol!
Dependent on his previous care he could, be anywhere from 6 to 12 weeks old.
Until he is around 12 months old, he should be getting 2 feedings per day, as much as he can eat in approx 10 minutes, each session! He should be eating live food which is no bigger (in length) than the space between his eyes. These should be dusted with calcium 5x per week and vitamins 2x per week. In terms of salad, he probably wont eat much as a baby so dont worry too much about that - just make sure there are greens available to him throughout the day.
He is a little cutie - and such a little personality! You can just see him saying 'this is my rock' and that fierce little open mouth shot is just too cute!
Good luck with little Marley
T