Is there a human soul? Of course. Just look up the people who have had "out of body" experiences. They often come back with verifiable information that their material senses couldn't possibly have detected. That rules out hallucinations! Besides, why do they always start with coming out of their bodies? Do they do that when they fall asleep and start dreaming? No!
Do we have immortal souls? I haven't lived long enough to tell. All religions except Secular Humanism believe so. Even Buddhism, which has no god, believes something continues on after physical death.
Not everyone who dies or gets knocked unconscious report going anywhere or doing anything when they come back. It is just so much time missing from their lives. But that doesn't discount those who do!
There are those who come out of body, "see" what is happening in other places and travel to "heaven" and back. Is the verifiable information on earth evidence of something, but information about "heaven" pure hallucination? What if they get new information in "heaven" that can be verified on earth? There are cases of this.
Wherever they go in "heaven" seems to be a forecourt. They are given metaphors they would understand for a lot of the incredible things in the real heaven. There is some time distortion since they are halfway between universal time and eternity time. People who have permanently died come to see them there. People who haven't been born yet come to see them there. Wild.