After finishing Janko Mišić Elementary School in the town of Samobor, he enrolled in the Nikola Tesla Education Center for Automation, Energy and Process Engineering in Zagreb.

In 2016, Beljak completed a postgraduate specialist study in Foreign Policy and Diplomacy at the Faculty of Political Science of the University of Zagreb.

[7] In 2010, he was charged for illegal and unconstitutional formation of a parking lot in the courtyard of Perkovac 22, one of the main Samobor roads.

[10] In June 2016, the HSS left the centre-right Patriotic Coalition, led by the Croatian Democratic Union (HDZ).

Beljak, who was elected to the Croatian Parliament along with four other HSS members, decided to give support to the new government "for 100 days".

He is in favor of abortion rights and refuses to classify the HSS as conservative, stating that "all political parties should be somewhat liberal".

[16] On 12 January 2020, he made a comment regarding extra-judicial assassinations of Yugoslav Communist regime's political opponents committed by the Yugoslav Secret Police (UDBA) outside Yugoslavia between 1945 and 1990, tweeting that the number of "over 100" executed was "obviously not enough", and claiming that the people who escaped UDBA's reach were "fascists" who "made all the wars from 1991 to 1999".