Proton and neutron has a size of 10-13 cm (approx. 1,5-2 fm). The diameter of the electron may be cca. 10-17 m but this is only a calculated value and is not very sure.
Protons and neutrons are not in electrons. protons and neutrons are the center or core of an atom. the electron(s) is/are found in a "cloud" along the outside edge of the atom. Hydrogen for example...