Global Entry interview locations are at many major hub airports. Just take care of the application & preliminary approval first-- takes about 1 week and the $100 application fee.
The next step is to schedule the interview. I found out that it is possible to do a “walk-in” interview on a different day, provided you do have some interview date scheduled.
I suggest u aim to do the interview in conjuction w an upcoming trip that connects thru a major hub. Just budget a generous amount of transit time in that airport. They’ll process walk-ins once they’ve taken care of the scheduled interviews. That means you may have to wait quite a while for your turn.
The interview lasts 10 min and consists of asking about your travel plans and then taking your photo & fingerprints.