How do you make a distinction between the language they speak in Castile(s) and the one that use in other regions and is official in all Spain? You can't. I sp

How do you make a distinction between the language they speak in Castile(s) and the one that use in other regions and is official in all Spain? You can't. I speak Spanish but I'm not Castilian and has no relationship with those two regions (Castile-Leon and Castile-La Mancha).