How can I tell if a younger male stray is neutered?

I found this poor baby scared in the cold. I have never had a male cat so I’m not quite sure how to identify it at all and can’t really afford a vet visit nor schedule even swinging by somewhere for quite a bit. On top of that, All vet reddits don’t allow attachments. I’m trying to find a place for him but I already had a female stray I had found earlier in the year too and I’m scared they will mate but can’t just keep him locked up in a closet or something. I also don’t know what to tell the people I’m asking to adopt him. Thank you.