Whats the difference between an atom and an ion?

An atom is the fundamental unit of matter and it contains an equal number of protons and electrons in its nucleus which makes it electrically neutral. An ion however, is an atom containing an unequal number of protons and electrons which means it will either carry a net positive charge or negative charge depending on whether there are more electrons or protons.

atoms are neutral or they have equal number of proton and electron but ions can be cation(positively charged) or anion(negatively charged) based on the number of electron the atom lose and gain respectively

it's all four options.