My partner and I hesitated for a long time before getting a puppy, because we both work full time we thought it might be cruel to leave one at home by himself during the day. Because my partner has an RDO during the week, our puppy Judd is home by himself for about 8-9 hours 4 days a week.
But we do the best we can, and to be honest Judd doesn't seem all that worried about it - I haven't seen any signs of separation anxiety and he doesn't whine or howl when we leave him. We make sure we play with him and walk him in the mornings before we go to work, then we play with him for at least 20-30 minutes when we get home as well as taking him to the park for a run and to interact with other dogs.
A lot of people say that if you work full time you shouldn't get a puppy, but I disagree - we provide Judd with a warm loving home and give him the absolute best care possible. Obviously leaving him home by himself 4 days a week is not ideal but both of us need to work to pay the mortgage so its the best we can do.
We do see some signs of boredom when we get home, which is to be expected - usually nothing more than a few holes in the garden, and he's chewed a few of our sprinklers. Make sure you get your puppy lots of toys, keep some aside though and rotate the toys daily so he's got different toys every day. We got a doggie door installed in our glass sliding door in our laundry so he's got access to the laundry if its cold or rainy, plus we give him bones, pigs ears, and other chew treats as well as lots of fresh water.
I think Judd sleeps most of the day while we're at work because when we get home he's got a LOT of energy, so we just make sure we play with him lots and take him for lots of exercise - if you do the same sort of thing your puppy will be fine