Is their beginner races for 250 cc dirt bike?
There are always beginners classes no matter where you happen to be as people have to start somewhere and they do start mx at all different ages including veterans. So no matter what your age you will find a class that is suitable for you, they may just have a different name depending upon just where you are in the world. You will also always have people who appear to be better than a beginner in some of those classes as it depends upon how each country, state or even local track does there gradings and some do love to stay in the lower grades simply to get hold of a trophy and not caring if it is a beginners one. Just get plenty of seat time practicing before you attempt to race and make sure you hold your line on the track and not wander. Don’t look over your shoulder as those coming up faster from behind will know what they are doing and pass cleanly if you don’t do anything erratic.