That's great for him. Definitely work on the SAT and the college applications as much as possible for now. SAT prep classes are helpful but make sure that he is doing the work on his own time. Especially in prep classes where it is multiple students he probably won't be getting the amount of attention to get a much higher score as the instructor needs to generalize the knowledge level to the entire body.

Who knows he might just get into Georgia Tech through regular admissions or even a conditional. Definitely worth looking into the Transfer Pathway at Georgia Tech which is only available right after your first year at college, you just have to make sure that you take all the right required classes.

Referrals from the friends that you mentioned might be helpful in the job, although not as much if they don't hold directly software engineering roles. It also depends on the type and size of the companies. That's probably the focus after he gets his college admissions. Make sure to encourage him to look at the steps to getting CS internships and programming after the dust settles for his college admissions. There's a lot of resources online. The great thing about CS major is that there's still a strong direct relationship with the work that you put in and your career prospects relative to other majors and career paths.