Puppy biting and growling

Hello everyone
I'm the happy and proud owner of a little puppy staffy collie cross called hunter, well his mother was a staffy collie cross but his dad is a pedigree staffy, he's a lovely and pleasant enough dog but recently we're having a few issues with biting and growling, he's 14 weeks now and we've had him since he was around 7weeks but recently he seems to be going out of his way to get a bite in at you. iv read about teething but I'm not sure if this is the case he's got plenty toys to entertain him and me and my fiancé are always playing or walking him as I know puppies are very needy and demanding so I don't think it's boredom either, I'm pretty stuck with how to approach this as iv tried everything but he just doesn't seem to learn.
Any advice would be greatly appreciated.
Thanks

He's a puppy and puppies play using that mouth full of sharp little teeth, all totally normal. Some people make a yelp when they do this and replace the hand, leg, torso with a toy to reinforce that it's ok to bite that but not humans.

It's very important that everyone in the house treats Hunter in the same way so he gets the message. Also, keep the hands out of Hunters way, he will see them as a toy. Simply stand up, put your hands under your arms and ignore him until he stops.

The growling sounds like play too, it's very unlikely to be aggression at this age.

When you get a min pop along here and say Hi:-
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Like any babies, dogs explore with their mouths too. As Ian said, when your pup goes for your hand, simply replace with something thats his instead. If its consistant, stop playing all together and ignore him. Then continue to play a little later. This kind of behaviour takes time to break but you will get their in the end. I also used a simple 'ah ah' everytime he nipped and removed my hands.

We've tried telling him no then replacing it with a toy but he doesn't seem to pay attention he just keeps going to bite you instead, but when he's been naughty and we've told him no and put him in his cage as seems to get scared of me and won't come near me, I just want this little issue to be sorted as soon as we can as we have a baby due in around 6 months, he's a pleasant dog with other people and kids I just wouldn't like the thought of him nipping anyone else never mind a child

You will get there... He's learning.

Do you crate him of a night ?... Be careful that he doesn't start associating the crate with being told off. That should really be his safe place, like a den if you like. Keeping it his safe space will pay off in the future. If you need time out space it would be better if you could put Hunter in a different room.

Yea he sleeps in it on a night, if he knows he's going to be told off which when he's doing something wrong he usually knows he's doing it cause before you even get to say NO! He'll run straight into the kitchen into his bed, which is frustrating because he seems to know he's going to get wrong for what he's doing but just does it anyway

Trust me... If your consistent he will learn what's right or wrong.
Reward good behaviour, ignore bad.

As above it just takes time and consistency, promise! They are such sociable pups they do really hate to be ignored so a firm 'NO' and either getting up and walking away or just pick him up and put him behind a stair gate or in another room. Just for a few seconds to calm down should be enough for him to catch on.

Have you started training with him? We found that when Bane got snappy and over excited, if ignoring him didn't work, we would distract with training. So we'd ask for a sit to try and get him to focus and then reward for listening and being calm.