It's not so much about training the dog, but you guys.
You should find out about which que words, or commands were used in his training, which language this was done in. Also which methods were used, which corrections, which prey items were used for rewards, even which treats were used. As consistency in training is key, if you cannot know any or all of these things, then a basic class would not be a waste, though he should progress quickly, providing you do, and quickly become consistent in both your command words and the tone with which you speak them.
If a clicker has never been loaded, and you choose to use one, you'll have to load it, i.e. C/T (click, then treat) until the sound comes to mean a good thing is to follow. It "marks" a good behavior.
Without know how much you know about shaping behaviors, or dog training, I assume it's little, or you would not have purchased one pre-trained. But this doesn't mean you don't still need to learn much, only that it ought to be easier, as there will be little confusion as to who is teaching whom.
I'm not being a smart a$$, Hank, they all have plenty to teach us, and while we may think we're going to teach a pup a thing or two, by the time this creature is an old and greyed beloved companion, there is not a single handler out there who hasn't come to realize who taught who the most, and only the most arrogant think it to be the human who held the Phd. in life with a dog.
Your good fortune is, your's has some experience. Let's hope it's been a good one you can know something about, or easily ascertain over time must have been positive.
