I know my understanding of quantum physics is below basic, but they are quantum computing, which I’m not sure of the difference.
A fundamental insight of quantum mechanics is that photons and it seems nearly all matter on the smallest scales have a dual nature as both particles and waves.
In the simplest example, light passed through a carefully constructed double slit interferes with itself so as to produce a diffraction pattern of dark and light that indicates light is in the nature of a wave.
The same effect can be demonstrated with waves on water or even sound waves. That is simply how waves work, with waves reinforcing or cancelling each other.
Yet light also consists of individual particles called photons. And when the double slit experiment is more closely analyzed, the waves of light can also be identified as consisting of discrete photons -- and those photons interact with each other like waves.
The mind boggling part is that photons passing through the double slit experimental arrangement are entangled and "know" where their colleagues in the wave are and to react depending on whether the other slit is open or blocked. Thus such photons react instantaneously to interfere with or reinforce the photons that are potentially passing through the other slit.
Quantum entanglement and quantum interference are deeply complicated and philosophically troubling. Einstein called entanglement "spooky action at a distance" and spent decades fruitlessly trying to disprove its existence.
Moreover, after decades of experimentation, it has been demonstrated beyond question that for particles to be entangled or for their behavior to be analyzed requires an observer. More broadly, without an observer, quantum states are also indeterminate.
Thus it is said of Schoedinger's cat that if it is used in an experiment so that it lives or dies depending on the chance of a quantum event happening, until the experiment is checked, in a philosophical and practical sense, the cat might be either alive or dead. The implications of this are either trivial or profound depending on the specific theory of quantum mechanics one prefers.
As for quantum computing, in concept, it relies on quantum entanglement to carry out certain types of mathematical operations. Broadly, particles are made so that they are entangled with each other and programmed so that only one combination does not cancel each other out through quantum interference. That one valid combination is the answer sought.
Again, as with the double slit experiment, the entangled particles in nature or in a quantum computer "know" in some fashion that they are entangled with other particles and react to what is happening with them. The larger implications can be taken as meaning that some form of consciousness pervades all matter, with some referring to modern quantum mechanics as a philosophy of panpsychism.
To get back to your suggestion that thoughts might affect a quantum computer, in quantum mechanics (so far at least) even though an observer is needed to determine a quantum state, the observer has to act, not just think about acting. Granted, the connection between our minds and our actions in the world requires a connection between thought and matter, that is a different matter than having thoughts alone affect a quantum computer. So far at least.