Simple answer: Some do. Some don’t. Complex answer: Hinduism is a massive religion that has developed over several millennia, and it has many sects and deities with various avatars, vehicles, etc. etc. with many volumes of philosophy, psychology, literature, mythology, doctrine, and more.
So, there’s a lot of variety within it and, sometimes, apparent contradiction. For example, there are Hindus who believe in the Trimurti (Brahma, Vishnu, Shiva), with representations among some 2 million other deities. World renown yogis like BKS Iyengar and K Pattabhi Jois, for example, made their rituals in accordance with Vishnu and Shiva, respectively.
But there are also Hindu atheists who, while not exactly rejecting Brahman (the unchanging reality, not the God), reject the Vedas as well as the idea of a personal (and personified) God.
Some Yogis ascribe to the idea that everything is either Purusha or Prakriti (Samkhya school of yoga philosophy). Other sages point out that it isn’t an either or thing at all, it’s just one thing… Except they wouldn’t say it like that…they would just say it’s “not two things” and say nothing else. This is known as Advaita (Vedanta school) which literally means “not two”.
Anyway, both of these reject the idea of a single deity who created the world.
It’s best not to look at yoga as a theistic religion. Much of Hinduism is definitely theistic… You can pray to Ganesha and he’ll solve your problems, for example. But it’s better to understand yoga as a philosophy and mind-science. Yes, it comes out of Hindusim, but so does Buddhism… And that’s definitely nontheist. …or, at least it’s supposed to be. It seems that, over time, some sects of Buddhism (I’m looking at you Mahayana) began to worship the Buddha as a representation of omnipresence.
The Aghori Sadhus are interesting (for many reasons!) in that they believe in Shiva but also embrace Advaita. It’s a little confusing, but the idea is that if Shiva is perfect and in control of everything (all causes and effects) then to deny anything is to deny Shiva. But you can’t deny the omniscience and omnipotence of the Supreme Being! So, for them, everything is Divine and there is nothing that isn’t. (If that sounds a little like Tantra philosophy, the similarities are there, including transcending social taboos etc.) but the Aghori take part in rituals and customs that involve things that most of us avoid, like hanging around the cremation Ghats, smearing ash on themselves, and eating their food out of (human) skull bowls. For them, this is a way of destroying the stuff (shame, hatred, greed, etc) that attach their soul like a noose, bonding them in a cycle of reincarnation, until they achieve liberation.
Like I said, it’s complex. www.NomadYOGI.com