This question is not as simple to answer as it seems. But according to what I read i hindu mythology books and what my grand parents taught I could answer a little bit for the same.
According to our Hindu culture, which is itself plural, with a vast collection of customs and beliefs of numerous communities, over many periods of history, there is no single story of creation. There are many stories, some from the Vedas, some from the Brahmanas, some from the Puranas; some are philosophical, based on concepts, and others are narratives based on characters. One can sense something common in all, but there is a great deal of variations.
So, beginning refers to the beginning of a phase, not beginning of the world itself. When we speak of ‘creation’, we have to clarify, are we speaking of the birth of matter, or birth of consciousness, or birth of living creatures, or birth of culture.
we refer to Brahma as the creator, we are referring to the birth of human culture, through the ritual of culture. Culture goes through four phases of childhood (Krita), youth (Treta), maturity (Dvapara) and old age (Kali) before dying (Pralaya) after which there is rebirth. The death is imagined as a flood, and the only thing that survives is the first human, Manu, and the Vedas, saved by Vishnu. This is a recurring event.
Brahma is also called Prajapati, the father of all living creatures. And so from his mind are created ‘mind-born’ sons, the sages, referring to asexual reproduction. After which come sons who marry women and produce children. Rishi Kashyapa, son of Brahma, marries many women who give birth to different kinds of creatures, according to Puranas. Timi gives birth to fishes, Kadru to snakes and Vinata to birds. But it is never clear where the women come from: are they from Brahma’s body or elsewhere? The Brahma, and all male forms, seem like metaphors for the mind that is planted in matter (represented as women) to create embodied life.
This union of a male and female form, of mind and matter, is a recurring theme in Puranic tradition, especially after the rise of Tantra. Shiva cannot create the world without Shakti; without her, he starves. This world of Shiva and Shakti is nature. In the Gita, this duality is denied. Krishna claims that he is the source of life, that he has two ‘wombs’ (yoni), which are mind and matter. Some people prefer using the word consciousness instead of mind.
What comes first, mind or matter? In the old Vedic hymns, over 3,000 years old, the most famous ‘creation’ hymn is highly skeptical if this question can ever be answered for even the ‘gods came later’. This skepticism is found in Upanishads too, although many attempts are made.
Later, in Tantras, we are told that matter came first as the Goddess, and from her came the mind, taking three male forms: Brahma, the priest; Vishnu, the king; Shiva, the ascetic. Brahma sought control of the Goddess, and was beheaded. Shiva sought to reject the Goddess and was enchanted and turned into husband. Vishnu became caretaker as well as beloved of the Goddess. Brahma’s desire to control the Goddess is given as the reason why he is not worshiped.
Shiva worshipers rejected this idea and tell the story of the pillar of fire, embodiment of consciousness, that has no beginning or end, whose tip Brahma could not find when he took the form of a swan, and whose base Vishnu could not find when he took the form of a boar. Thus, Shiva is the infinite origin around which all finite forms take shape.
These myriad ways of looking at creation open up our mind to various possibilities and do not fix it to one way of looking the world. Thus, the dynamic diversity of our culture manifests itself oneself once again.