A carbon-$$12$$ atom has $$6$$ protons, $$6$$ neutrons, and $$6$$ electrons. How many protons does a carbon-$$14$$ atom have?
Carbon-$$12$$ and carbon-$$14$$ are isotopes of the same element, carbon. This means that they have the same number of protons and the same number of electrons - just different numbers of neutrons.
The atomic number of an element is the number of protons or the number of electrons, it has (since, in a stable atom, the number of protons and electrons are the same).
All isotopes of carbon atoms have $$6$$ electrons and $$6$$ protons.
A carbon-$$14$$ atom has $$6$$ protons, $$8$$ neutrons, and $$6$$ electrons, so its mass number is $$14$$ and its atomic number is $$6$$.