Peace be upon you. According to Grand Ayatollah Sayyid Sistani (may Allah protect him), it is obligatory to place the palms on the ground completely, as much as possible, with caution being required. According to Grand Ayatollah Sayyid Khamenei (may Allah protect him), during prostration, it is necessary to place the forehead, the palms, the knees, and the tips of the toes on the ground. For further details, you can refer to the sources: 'Minhaj al-Salihin - Chapter Six on Prostration' and 'A Treatise on Prayer and Fasting - Issue 237'. May you be successful in all good.