Aw.. 8 weeks is so tiny
First and foremost - nothing ever is instant with them except for their reaction and quick wit. Everything takes time. Teaching his name alone may take a few days to a week and not very reliably. Practice is everything. Also keep in mind that puppys have very little attention span. Train for a minute or two, and play a bit, then let him play alone and he'll probably be asleep for a bit. Let him wake up and play for a bit on his own, then train for a few minutes, rinse and repeat. Of course with frequent potty breaks.
You need to establish some routine - they love that. And try sticking to it.
Make sure everyone in the household follows the same routine. Consistency is the key.
Dogs learn by association (at least for the most part) - they associate actions to our verbal commands, so clear communication is the key. All you left to do make them do what you want, then give it a name - command.
If you already do that, that's great! Then just be patient and give it some more time. And try not to teach many commands at once - just focus on one at a time. They learn faster and more reliably. Keep using everything he knows regularly so that he doesn't forget.
Another idea, if you can afford of course, maybe take 1-2 private lessons in-house. This way you don't need to worry about the shots, and even in one lesson an experienced trainer who loves what they do will show you the ropes and how-to's.
Good luck and keep him happy!
)) He is a puppy still. Play more train less. Show him love, fun. Restrain when needed but firm and calm. Like annabirdie said, it's time for bonding, earning trust. And trust goes both ways. Show him that you are a worthy replacement to his own mom
And before you know it, he will be running happy when you call him.