There are two alternatives to get to Cabadbaran City. One is to fly from Manila to Surigao and then take a bus which is approximately 90kms, or about a two hour bus ride.
The other option is to fly from Manila to Butuan and take a bus which is approximately 40kms, or just over an hour bus ride.
Philippine Airlines (PAL) fly to Surigao from Manila once daily and also fly to Butuan from Manila once daily. Flight time is just under 90 mins.
Unless you are visiting someone, or diligently trying to backpack around Mindanao, don’t go out of your way to go to Cabadbaran City as there isn’t really much to see or do there, and it certainly isn’t geared up for tourism at any level.