I think if you're doubting wether you have the time and effort to care properly for a dog, then the answer is no don't get one. They're a blessing to have and great companions but are also very time consuming and expensive. There's food to buy, vet bills, worming tablets, inoculations, leads and collars as they grow, toys, beds/bedding, puppy training class (good for socialising your dog at a young age), the cost of the dog itself unless you're adopting. If you're adopting be sure it's safe around children.
On the upside you get a companion that will never judge you and will love you unconditionally. Until the 26th of December I had 4 dogs. Unfortunately my Briard Hugo developed internal bleeding on Boxing Day and I was forced to have him put to sleep. He lived to a good old age of 14, which is excellent for a big dog. And I can honestly say the hardest thing about having a dog is losing them

What kind of breeds are you thinking of?
I still have my three other dogs, Mylo, Alfie and Jasper, which are a Cavapoo, Briard and Toy Poodle (not cut like a poodle). Very intelligent dogs.