You need to go sit at a G2G briefing at your Ed center. There are three different G2G programs and several other commissioning routes depending on your end goal.

Great to hear. I also went G2G AD Option. So to answer ur questions, yes your wife can be with you and yes you pick ur college as long as u are accepted and it fits within the tuition cap set. It was $15k when i went through. So you are pretty much just a college student. Most likely your PMS(Professor of Military Science) will put u in a leadership role to help mold those 1 & 2 year students. Other than that obviously you will take ur two APFTs each year. You will go back on active duty when u are done and u can still compete for what branch u want. If u leave wherever u are at now it is a PCS move and ur BAH will be based on the location u go to school. If u r close to a base there may be an opportunity for base housing but i recommend finding a place out in town maybe close to the college. Hope that helps and good luck. Feel free to reach out with any additional questions. Oh and yes ur are paid as a SPC or SGT depending on ur promotion and u also maintain ur (P) status while in school. U accrue leave and time towards retirement if u stayed in the traditional retirement plan.

Everyone has just about mentioned everything. The only thing that I can add is that while you are getting your packet together, make yourself highly competitive. Continue to get good grades in your academics; have the highest GPA you can attain when you drop your packet. Continue to PT hard, again, you should have your highest APFT score card when your packet is reviewed. Go to some Soldier/NCO of the quarter boards and do well in them. Go for the SGT Audie Murphy or SGT Morales boards. You want to make your SAL worksheet highly competitive and dressed up with hard stats. That shows that you really want it.
I went G2G after 10 years of service. Best career move I could have ever asked for. Best of luck with it!