Is it acceptable to pray, recite the Qur’an, and perform acts of remembrance (adhkar) without understanding their meanings and interpreting their verses, and is it necessary to know the pillars of prayer for it to be accepted?

Deeds are accepted under two conditions: sincerity to Allah and following His Messenger (peace be upon him), as Allah the Almighty says: "So whoever hopes for the meeting with his Lord, let him do righteous work and not associate anyone with the worship of his Lord." It is not a condition for the acceptance of prayer that a servant knows the meaning of the verses he recites or the dhikr he repeats, nor that he knows the details of the pillars and obligations of prayer. If he performs it sincerely for Allah and following His Prophet, his prayer will be accepted. Al-Buhuti reported that if someone does not know the difference between a pillar and a condition, or a fard (obligatory act) and a sunnah (recommended act), his prayer is still valid. However, learning the meanings and having presence of heart brings greater reward and induces more humility.