Hello and welcome!
First of all, I would encourage you to check out this sticky on the barrel forum. It's got lots of great information for newbies like yourself. Barrel Racing Exercises and Drills.
is key to training a barrel horse. You have to learn how to walk, before you can run, right? One of the easiest ways to ruin a horse on the barrels is to push them too fast too soon. You'll get sloppy and lose form and create bad habits. Depending on how well broke your horse is, it can take anywhere form 6 months to 2 years to have a finished barrel horse (usually it is always closer to that 2 year mark). So that you realize it is not something that happens overnight. It's takes lots of specialized training just like any other sport.
And lastly, find yourself a barrel racing trainer to work with. We can help you with what we can here, but it is the internet. Would you trust an airline pilot who learned how to fly an airplane because he learned it on the internet? Heck no! You'd want one who had hands-on training. So why should barrel racing training be any different? Hands-on training is the best way to go.