Sounds like he is now sexually mature and ready to be neutered, for sure.
Unfortunately, I do have experience in this matter. If it does get stuck out, keep it lubricated. KY will do. Usually the little hairs get rolled inside the skin and keep it from closing back over his penis. Gently pull the skin back down the shaft and try to make sure the hairs are all out and then gently slide the skin back up toward the tip. If it is out too long or gets too dry, it can swell up and you won't be able to get the skin back over it.
I swear the next part is true. If it is truly stuck out, pour granulated sugar on it, and wait. It could take 30 minutes. The sugar draws the moisture out so the swelling goes down and the skin can cover the penis again.
Hopefully you will get him fixed and that will take care of it. Good luck.
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