I think the fact that your son's pediatrician
is not very concerned about the finding of scoliosis
is a pretty good sign.
As you probably were told, scoliosis is an abnormal curvature of the spine. A minor amount of scoliosis is actually surprisingly common and, generally speaking does not require any intervention other than periodic checks to make sure that the curvature is not getting worse (if it is going to get worse, it tends to do so around growth spurts).
You are also right that more severe cases of scoliosis may require treatment. Treatments for more severe scoliosis can include bracing procedures to keep the spine aligned. In the most severe cases, corrective surgery
is often also indicated.
Your son's pediatrician can keep an eye on the scoliosis and the regular check up visits. If at any point the amount of scoliosis begins to be concerning, your pediatrician at that point can refer you to a orthopedic spine specialist, who can then perform further testing and help determine whether more aggressive management is needed.
Please talk to your pediatrician soon and regularly thereafter, as they should be able to help.