This has to do with Education deductions/credits. It is sometimes better in the "whole family" sense for a dependent eligible to claim the credit to file their own return to claim the federal credit. That means they are "claiming themselves" and so the parent cannot also claim them as a dependent on their federal return.
But, that doesn't apply to states like California where that dependent doesn't "claim themselves" on their own Calif return, if any return at all. If the person is otherwise a qualifying dependent then the Calif taxpayer may claim such a dependent even though the person was not claimed on the federal return. The TT/Calif screen you see is to add such dependent(s) to the Calif return.
This doesn't sound like it applies to you since your sons don't appear to be qualifying dependents for your federal return. That makes them not qualifying dependents for your Calif return as well.
