How can one avoid major shirk in contemporary society, and is performing two rak'ahs of repentance daily with the intention of disavowing shirk a means to achieve this, especially given the intense fear of falling into it?

To prevent polytheism (shirk (definition)), one must always seek refuge in Allah and seek His forgiveness from it, and recite the well-known supplication: "O Allah, I seek refuge in You from associating anything with You knowingly, and I seek Your forgiveness for what I do not know."

Seeking help through prayer and asking Allah through it is generally prescribed, based on the Almighty's saying: "And seek help through patience and prayer." There is no legal evidence for performing two specific rak'ahs daily to seek guidance and steadfastness, except when a sin has been committed.

Maintaining the obligatory prayers and the two rak'ahs of Fajr is sufficient for asking Allah for guidance, steadfastness, and deliverance from shirk. It is also recommended to recite Surahs Al-Ikhlas (definition) and Al-Kafirun in the two rak'ahs of Fajr. The recitation of Al-Fatihah in prayer is divided between the servant and his Lord, and it contains a request for guidance from Allah.