Purusha myth :
In the Rig-Veda, Purusha is described as a primeval giant,], that is sacrificed by the gods and from whose body the world and the varnas (castes) are built. He is described as having a thousand heads and a thousand feet. He emanated Viraj, the female creative principle, from which he is reborn in turn before the world was made out of his parts.
In the sacrifice of Purusha, the Vedic chants were first created. Heaven and earth were made and the horses and cows were born.

• the Brahmins were made from Purusha’s mouth.
• the Kshatriyas from Purusha’s arms.
• the Vaishyas from Purusha’s thighs.
• the Shudras from Purusha’s feet.

This all were created only from ¼ of Purusha. The remaining ¾ of Purusha was the immortality of the heaven.

Prajapati myth:
Prajapati in Hindu mythology is the primordial lord of creatures, and is mentioned in Vedic, epic and Puranic literature. In Vedic legends he is described in various ways as the creator of the world, and the creator of heaven and earth, day and night and death. He did not know why he was born, was alone and wept. His tears formed the ocean, heaven and earth.

Hiranyagarbha (golden egg):
Hiranyagarbha, ‘Golden egg’ or ‘golden womb’. This egg was floating in the cosmic ocean. From this egg came Brahma. Brahma made man and woman. The other name of Brahma is Narayana, the one who arose from the water.
In the Rig-Veda Hiranyagarbha “is said to have arisen in the beginning, the one lord of all beings, who upholds heaven and earth, who gives life and breath, whose command even the gods obey, who is the god over all gods, and the one animating principle of their being.