Hi Amber and welcome to BYC We're so happy you've decided to join us
I raise my CX on an 18% protein broiler mix from end to end, but it really depends on your goals. Talk to your 4-H rep and see what they are looking for. If their recommendations are way different than what I do, I would follow theirs. I raise for optimum meat production with lowest mortality rate. I also prefer chicks from McMurray hatchery. Depending on the strain of birds you've gotten, you may need to adjust your feed approach.
While in the brooder I feed two to three times per day and will give them a few meal worms a couple of times per day to get them moving about. Mine stay in the brooder 3 weeks and then 35 days on fresh grass. I also only feed what they can consume in about 45 minutes twice per day once they are on pasture. I move them at least once per day when they are on pasture.
We are glad you joined our flock!
We're so happy you've decided to join us 
Enjoy your time here at BYC! 
