Rājyābhiṣeka is a special ceremony that happens when someone becomes a king or queen. It is like a party where everyone celebrates and the new king or queen is given special things.
During the ceremony, the person becoming king or queen is given a special oil made from sacred plants, which is put on their head. This oil is said to give them power and make them a good leader.
Then, they are given a special crown made of gold or other precious materials. This crown shows that they are important and in charge of the kingdom.
Other people who are important in the kingdom, like priests and leaders, also participate in the ceremony. They give blessings and prayers for the new king or queen so they can be successful in leading their people.
Once the ceremony is over, the new king or queen is officially in charge of the kingdom!