Fernández was born in
Santiago de Cuba, where he studied his first and second education. In 1947 he graduated from the Cadet School of Cuba and also from the Artillery School as well as from other courses of the General Staff in Cuba and at
Fort Sill in the USA.
From March 10, 1952, he took part in different conspiracy activities and movements against the
Batista tyranny with different military and political groups, until 1956 when he was caught when the conspiracy movement called “Los puros” was discovered. He was judged and sentenced to prison at
Presidio Modelo on the
Isla de Pinos (Isle of Pines), where he was until the Triumph of the
Cuban Revolution on January 1, 1959.