You'll do 2 courses at Sheppard. 1st is a Heavies Fundamentals (Fundies) course which is very broad. Mostly general aviation theory and principles. A lot of Air Force specific terminology on what to "properly" call things. The second course is your C-130 specific course. You'll learn all your basic 3 level tasks and flight line servicing. You'll learn all your flight deck panels, hydraulic systems and servicing, very basic Allison T-56 Turboprop fundamentals and servicing, cargo compartment configurations, aircraft marshaling, wheel and brake changes, and a ton of other things. The school house is pretty nice and has a lot of trainers inside. When you go to LRAFB you'll do a 2 week OJT on the flight line. You'll refuel/defuel, marshal running aircraft, and mostly just hang out till your ready to get home.
Many of our ANG crew chiefs have gotten their A&P but most fill full time technician slots within the unit. One of the biggest things you'll be missing out on being a crew chief is we don't do any sheet metal work and you'll come out of school with very basic knowledge of the engine. Most people have said to try to work with your engine and sheet metal shops to help out with those specific areas on the A&P exams.
You'll receive a lot of college credit from the CCAF and there is a program with Embry Riddle that allows you to get a degree in Aviation MX with only about 60 hours after completion of your CCAF Associates. I'm not familiar enough with the CCAF to A&P program to comment on it.
Hope this was helpful. Good luck.