Hey Mdeni-
When you override the class, you can call the parent’s constructor with a Super call, which would run SetToDefaults the same way UGameUserSettings does in its constructor. An example of this can be seen in the UGameUserSettings constructor where it calls its parent constructor (which is UObject). Additionally, if you are overriding the SetToDefaults function itself, you can call Super::ResetToDefaults(); inside your overridden function to call the parent implementation whenever your version of SetToDefaults is called.
Cheers