forest fire fighting

can anyone tell me how old u gotta be to fight forest fires?

I don't know for sure, but my guess would be 18. Contact your local US Forest Service office to find out. Even if you're under 18, you'll need to take the wildland red card class first, and that way, you will have it out of the way until you are old enough.

Also you can contact your state forest warden..You need to get your pack test then you would take your S-130 then a S-190 to get red carded.....as to go out of state on the big fires

Overall 18 is probably he universal age, at least for anything related to the feds. Each state has their own laws otherwise.
Federal Red Card Requirements for arduous level: Successfully pass the annual pack test (3 miles, 45 minutes, carrying 45 pounds, on flat hard ground, administered by certifying office), and take the NWCG (National Wildfire Coordinating Group) courses S-130 (Basic Firefighter Training, which should include Standards for Survival) and S-190 (Basic Wildland Fire Behavior).
The only way to get these is through a State or a Federal office that does wildland firefighting. Local Departments often do it, but they are being sponsored by a State or Federal office.
Your post does not say where you are, but your best bet is to check your local area departments as to who is State or Federally connected. It is way too late in the season to join a national crew which will get you the most experience, they do most of their basic hiring and training Jan-May, but you can check and see who is closest and get yourself in shape for next year. An alternative, depending on where you are, is to get with a local department that hires out engines to their state, who in turn sends them to national incidents. This is going to be a hot fire season, and some departments are always looking for people willing to work for a living.