I can't stress how important dog training is from the very first minute you adopt one. Your dog needs to know what to expect from you and you need to know how to communicate those needs. A good dog trainer can help you with housebreaking issues, leash walking, recall, sitting, and even a few tricks.
Consistency is also very important and can become an issue when one family member treats the dog one way but another family member treats the dog differently.
For example: you bring a dog into the home and one parent says absolutely no dogs on the furniture. Parent number two lets the dog on the sofa whenever they are watching TV. So when parent number one finds the dog on the furniture, has a fit, and yells at the dog; the dog becomes confused and can develop behavior problems due to the mixed messages and treatment.
Consistency continues in every aspect of the dog's life. It includes leash walking, bathroom breaks, feeding, sleeping, playing, and alone time.
Dog trainers are a wonderful resource when you get a new dog. Don't be afraid to consult one but do ask questions. There are many types of trainers and you need to find the right fit for you and your dog.
What is the trainer's style? Are they knowledgeable about dogs? Are they kind? Or are they controlling? Do they use a gentle hand? Or do they believe in jerking the dog around, rough handling, or use of shock or prong collars? Which way do you want to handle your dog?
With proper, consistent training, a dog can be your best friend. Trust me. Your life will be more manageable when your dog knows what to expect from you.