Answer:
Fission is a specific type of radioactive decay. It produces fission fragments, which cannot be specifically predicted, though general predictions can be made about them.
The original atom is broken into two new atoms that are very roughly each half the mass of the original. For example, in a nuclear reactor, when a neutron is captured by an atom of 235U, it produces an atom of 236U, which undergoes fission almost immediately. One example set of daughter atoms of the fission might be 141Ba and 92Kr, which have a combined mass of 233, just 3 lower than the mass of the uranium atom of 236. Other isotopes can also be released.
In addition to the daughter atoms, neutrons are released. In this example, there would be three of them.
Gamma rays and neutrinos are typically also released, but not alpha particles.
Another product is energy in the form of heat.