Munyai holds a Bachelor of Administration (Honours) in Public Policy as well as a certificate in International Relations and Political Economy from the London School of Economics.
A member of the African National Congress, he served as head of election research and as chair of the ideology, political education and training sub-committee at the Walter Sisulu Leadership Academy.
On 18 August 2021, Munyai was elected as the acting chairperson of the committee following Sibongiseni Dhlomo's appointment as Deputy Minister.
[4] On 30 January 2023, it was reported that Munyai and fellow ANC MP Mervyn Dirks had resigned from the National Assembly amid talks of a cabinet reshuffle by President Ramaphosa.
[5] Newly elected ANC deputy president Paul Mashatile was selected to fill the casual vacancy created by his resignation.