I would urge you to move to your land, get set up and do extensive research into livestock guardian dogs (LGD) before bringing one into your life. There are many things you will want to consider and learn in order to make your LGD experience a successful one for you and the dog.
Breed: There are many breeds of LGD from around the world, the Great Pyrenees is but one. There are many commonalities among the breeds, but each has its own characteristics. Some breeds use barking as the primary deterrent, others are more reserved. Some breeds have easy going personalities while others have a "hard", more reactive edge. Some of the breeds are quite aloof, others are more tuned into their humans. Some LGD breeds protect by staying close to livestock, others defend a larger territory and therefore tend to roam.
Training: Many people start with an LGD pup which will require 1-2 years (2 yrs for most breeds) of exposure, training and maturity before it will be ready to guard your livestock. Many hours of work and a positive approach to training is a must in order to build mutual trust and establish a partnership with these highly intelligent and sensitive dogs. The single most common cause of a failed relationship with an LGD is the mistaken belief that the new pup can start guarding from day one. The instincts are there but it is up to you to nurture and shape those instincts. This takes a lot of time on your part and a lot of maturity on the dogs part. Puppies play. Chickens squawk and run. Chickens can die in this game. Just as one would never suggest that a 5 year old child could be a responsible babysitter, so should we never expect a puppy to be ready to be a trustworthy guardian. Guarding poultry is the most demanding job, requiring the highest level of maturity from the dog. Acquiring a mature, well raised LGD rather than a pup is an option but not without its own set of challenges.
Behavior: LGDs bark. Some of the breeds bark a LOT and often bark more at night (when predators are active) than during the day. This can disturb your sleep and your neighbor's sleep. Please also note that the mindset and working style of an LGD are very different from the breeds of pet dogs we are commonly used to. LGDs have been bred for centuries to think for themselves and work independently of humans. This has resulted in dogs that will partner with people but will not always conform to our usual definition of obedience. It doesn't always matter to them what you as mere humans want in a particular moment. They have a job to do, so if they feel it is more important to do a perimeter check right now rather than come when you call, that is what they will do. This is not a fault, it is a feature.
Predator load: It is important to consider exactly what you will be asking of the dog. In general, LGDs work best in pairs. One dog should not be expected to take on a pack of coyotes or larger predators. Not a fair fight.
Fencing: A secure perimeter fence is a must for keeping the dog on your property.
I hope this gives you a starting point for more research into livestock guardian dogs. It is a serious commitment to learning and partnering when you bring these incredible dogs into your life. In the mean time, I would suggest building a secure chicken coop with a predator proof outdoor run for your chickens. Get to know the land and its inhabitants. You will soon know if it is safe to allow your chickens some free range time during the day when you are home. Locking them up securely at night and when you are not home goes a long way toward keeping them safe.