You really need someone at home every day I'm afraid. Very few dogs would be happy left alone all day - you might have serious destruction of your house as well as the inevitable poo and wee to clear up.
When you are in a position to get a dog then the choice puppy / rescue is one you really need to think through carefully. Puppies are pretty demanding and you will have to deal with training and house training - but then you get a dog where you know all it's background and issues. A rescue could be a lovely easy adult dog that just slots into your home and routine - or could be a traumatised soul needing hours of attention and training.
I've had dogs for 30 yrs. 11 to date, 6 from pups and 5 rescues. 3 of the rescues were a breed I know well and slotted into the family like a dream. Two were crossbreeds, one a dream in the house with kids, cats, other dogs, but could only be taken out on lead and muzzled (I had to pay another dog owners vet bills
) My current dog is a rescue. Got him at Easter, little terrier, butter wouldn't melt in his mouth when I saw him in the kennels.
This week - 9 MONTHS later- is the first week he's been off lead when out (I've been using a long training lead) and he's still not 100% on recall - but getting there. It's only been 3 weeks that he's been clean in the house - and still has the odd accident. He turned out to be a totally traumatised little dog. Who knows what his history was!
He's passed his bronze good citizenship award and we're working on Silver. The main reason for taking him was the realisation that he was TOTALLY unsocialised with other dogs. He didn't understand any of the signals other dogs were sending and was acting aggressively out of sheer terror.
He's now got some doggy friends we meet on the park and I've discovered he loves playing with puppies. He's been hugely rewarding, he's a total sweetheart. The person who first got him from the Rspca brought him back within 4 days as he'd had a fight with her sister's dog. Luckily for me and him, I was second on the list and am experienced enough to know the difference between real aggression and defensive fear aggression.
I would always encourage people to look at rescue dogs, but you might want to think about identifying a breed you really like, research it, meet some of them, and then approach that breed's rescue. Breeds like labradors and golden retrievers are obvious choices. But not right now, not while you are out for whole days at a time.