[matese]

I have always had female dogs, Cody is a rescue, a surrender, he was 2.5 yo when we hooked up. I have all his medical records, he was neutered when he was a year old.
If your pups testicles haven't descended yet I assume you'll have to wait until they do. I believe a male can still be neutered but it will become a surgery procedure instead of just a neuter procedure. From what I have read testicles have usually dropped by 5 months old so you have time yet.

The sooner you get him neutered the better. If he is humping, hiking his leg to pee, the longer you wait the more this becomes a habit reason why getting him neutered as soon as it is medically safe is best.
I believe my kid was neutered at a year old was due to finical issues as that was the reason he was surrendered.
Please tell your BF neutering is done to prevent testicular cancer, it also helps in indoor marking and leg hiking, most dogs will squat when the pee if neutered at an early age.
My boy squats when he pees, sooooo cute lol and has never hiked his leg to mark in the house.
If he was humping it was more likely due to him being excited over something, maybe a toy, if it was, remove the item that excited him.