Yes ANG (or USAF reserve) is the way to go if you want to be an airline pilot eventually anyway. Bottom line, the sooner you grab a seniority number the better.

You have a lot of research to do to figure out how to get hired off the street in the guard/reserves, but it could pay massive dividends.

Baseops.net has a lot of info, but do a LOT of reading before you dare to post a question over there lol.

You don't strictly need any previous licenses for any mil program, but it typically helps to have a PPL to compete for a slot. Generally guard is more competitive since you don't incur a 12+ year active duty obligation. Their screening system tends to reward initiative, having a PPL would count along those lines.

Also at this point don't go too hard over on any particular airline or airline sector... who knows what the landscape will look like when you get there. Stay abreast of the industry so you're ready to make a good decision when the time comes.