Ibn Umar reported: The Messenger of Allah(‎ﷺ), peace and blessings be upon him, said:

Islam is built upon five: to worship Allah and to disbelieve in what is worshipped besides him, to establish

prayer, to give charity, to perform the Hajj pilgrimage to the house, and to fast the month of Ramadan.

Ṣaḥīḥ al-Bukhārī 8