Soul is a very confused category. Firstly, what is usually meant is immortal soul. In the ancient world all beings were indeed considered to have souls (look it up!), but only humans that latter. In Judaism the immortality of anyones soul is disputed. And in Christianity we can see the theology of the soul is more influenced by Plato than Judaism. Aristotle had a particularly clear way of explaining the multiple soul, with supervening layers - able to be a source of causation downward through the hierarchy. Rational soul, above sensative soul, above vegetative soul. He argued against the seperateness of any of these from the body. And described them as types of pattern or organisation, which can flourish or decay. This is very like emergent layers of organisation, consciousness, nervous & sensory systems, and cellular being. The idea that the soul is some kind of magic timeless ghost can be traced at least to Plato, but owes more in philosophical detail to Descartes, and his disproven untenable dualism.
Turing addressed the idea of when we should consider a computer conscious. There are in fact many disputes over the validity and precise implementation of the Turing Test, you might want to look this area up in relation to your scepticism (also 'philosophical zombies', which is exactly the area you are talking about). Turing basically argued if something can behave consciously, it is conscious. And all we can do is evaluate & interrogate behaviour, not speculate about some kind of innaccessible ontic essence.
As babies, we develop our consciousness relationally. The ability to decieve and understand that others may have false beliefs is a crucial stage of children's mental development, that occurs around 3 or 4 years of age, without which this scepticism could not begin. Looking back at our own development then, we can see how we have become more complex in relation to a society around us of individuals already displaying greater relational complexity. The scepticism about consciousness in others is further undermined by the Private Language argument, the sophistication of our thoughts depends on language, which was developed and learned relationally. We can't view ourselves as the disembodied rational minds of outdated philosophies.
Denying full consciousness or souls in others doesn't have a good record. It was used to justify enslavement of Africans and native Americans respectively (doubt about Americans having souls was justified by them not being mentioned in the bible, unlike Africans). Statements like "all men are created equal" are not just philosophical, grounded in the lack of evidence to the contrary, but also politically sophisticated antidotes to our tendency to try and diminish those we disagree or are in conflict with, or wish to exploit. Such relations with others may seem appealing to some in some ways, but history has amply shown them to be destructive of potential, corrosive or morals, and to lead inevitably to war revolution and violent civilisational collapse. Philosophical backing for this can be seen for instance through Rawl's theory of justice, where a society must be set up in such a way that we would consent to be born into any position in it (for that society to be just). If we are truly equal, then any people in our society now would be justified in acting as you would, in their position. If the social contract with them is voided, then revolt, war, or collapse, will begin unless justice is done, and seen to be done.
No justice, no peace.