All dogs should get daily exercise. 30 minutes is a good amount of exercise for any dog.
Bigger breeds typically require more exercise than smaller breeds. You can also tell if your dog needs to be walked by his behaviour, i.e. if your dog is restless, he may really benefit from a walk or some form of exercise. This can help reduce destructive behaviours.
Exercise can also include playing fetch with your dog or using a toy that requires “mental exercise”, such as stuffing a toy like a Kong with a treat, or another type of toy where your dog has to figure out how to get the treats out of the toy.