The two closest towns are Alto Paraiso de Goias or to São Jorge but there is no direct flight there. So the best option to get to Chapadas dos Veadeiros National Park is to fly to Brasilia first and then either take a bus there or hire a car and drive yourself.
Cavernas do Peruaçu National Park
To get to Cavernas do Peruaçu National Park you should rent a car at the closest airport in Montes Claros.