Can one fulfill the obligatory duties and adhere to Islam internally while facing parental opposition until reaching adulthood and the ability to be independent?

Hasten to embrace Islam by uttering the two testimonies (Shahadatayn) and resolving to perform acts of worship, especially prayer (Salat). Conceal your conversion from your family until you are able to bear the consequences of announcing it. Do not delay embracing Islam, for death may come suddenly. It is sufficient for you to utter the two testimonies and disassociate yourself from polytheism (Shirk). Perform ghusl (ritual bath) once after the two testimonies and before prayer, and pray secretly according to your ability. Combine prayers if necessary, and you may wipe over your socks (for ablution). Ghusl is obligatory for ritual impurity (Janabah). Zakat (charity) and Hajj (pilgrimage) are not obligatory if you do not possess wealth, and fasting is only obligatory during Ramadan.