If you're interested in wildland firefighting, the training is much shorter, though still hands on. To be certified as a basic wildland firefighter takes about 40 hours (1 week). 2-3 day in the classroom, then 2-3 days in the field practicing skills.
Both often require physical prerequisites to ensure you are a physically capable of performing the duties. For the structural academy, you may need to pass a CPAT test, or something similar. For wildland firefighting, you will likely need to take an NWCG Arduous Pack-Test (a 3 mile hike in 45 minutes while wearing a 45lb weight vest.)
CPAT Orientation Video: https://www.youtube.com/watch?v=ofpD3Gy7SM4&t=