Spinning reels have stationary spools while the spools of baitcasting reels rotate as line is pulled off. This is fine as long as the spool spins at the same (or slower) speed than line is being pulled off. Without some kind of speed control the spool will spin faster and faster as line is pulled off. The result is a backlash. Fortunately modern baitcasting reels have braking systems that reduce the chance of this happening. As good as these are, they're little help if not used correctly.
This is how I learned to use a casting reel.
First tie on your bait.
Next, set the magnetic brake to about the halfway point. You'll usually find this brake on the left side of the reel.
ile holding the rod at about a 45 degree angle. No, it does not have to be exactly 45 degrees. Place your thumb on the spool and disengage the spool. If the bait drops like a stone apply thumb pressure to stop the spool and prevent a backlash. You'll need to increase the centrifugal brake. It's a usually found on the right side of the reel. If the bait did not move or stopped well short of the ground, loosen the centrifugal brake. You want the bait to slowly approach the ground, but not quite reach it.
To increase casting distance, once you're comfortable and confident, ease up on the magnetic brake. You'll need to set your reel each time you tie on a new bait. I know this seems like a lot to do compared with just tying on a bait and casting with a spinning reel. Once you get the hang of it, it'll become automatic and you'll have a new tool to use. Then again you may become a convert to baitcasters.