I'm assuming you mean a living organism somewhere in the universe, specifically. But, if there are other living organisms, then there is no reason why there couldn't be living organisms like humans.
Sure sure, such a thing as you describe and a myriad of other possibilities are of course possible - that is why I do not claim 100% certainty on that or any of my other answers - but I do not think such is the case.
That goes equally for your thought experiment about us being in a simulation created by some other intelligence. I do not claim that this is impossible, I claim only that there is insufficient evidence to convince me that this is actually the case.
I have previously admitted that I am hesitant to claim 100% certainty on most things and I will now say that the idea of Earth being the first birthplace of intelligence is the one that I am least certain about out of those questions you asked. I do however think that there is evidence that we may be the first, at least within our local group of galaxies.
As for what that evidence is i actually think it might be better to open a new thread, perhaps in the science or philosophy forum, rather than go into detail here if you wish to have that conversation. If not then I will simply say "I think the most likely possibility is that we are the first (at least within our local group of galaxies)" and leave it at that.
You think it is logical, in a seemingly infinite platform, that we are the first? We are proof that are type of intelligence is real and can exist. Wouldn't it be illogical to say we are the first?
Again I admit It is possible that other intelligences existed prior to ours, but I do not think it is in fact the case. Even you, and I am assuming here that you do not believe humanity to be the first example of sapient life, must admit that It is possible that we are the first even if you do not think it likely. After all in a scenario where there are... 'multiple generations of sapience' I suppose, for lack of a better term... Even in that scenario someone has to be first and that someone could be us.
It is therefore not about what is possible, since we both acknowledge both possibilities are possible, but instead It is about what is more likely. I think It is more likely that there have not been other intelligences before ours and you (I assume) believe It more likely that there have.
Again the specific reasons why I think this is more likely is something I would rather discuss in another thread, if you wish to have that conversation that is.
It just so happens that the existence and nature of intelligence (I am sure you have heard of the Fermi paradox) is something that I have recently (within the last few months) spent A LOT of time thinking about. In fact if you had asked me that last question this time last year I may well have given a very different answer.
An infinite setting makes more sense than a finite setting
There are multiple problems with the idea of an infinite past. Entropy is not the only such problem, It is simply one of the strongest and most well known.