The first 90 days with a new puppy involve excitement, adjustment, and rapid development. Early weeks focus on bonding, crate comfort, feeding routines, potty habits, and safe exploration. As the puppy grows, learning expands through simple commands, sound exposure, leash introduction, outdoor experiences, focus training, and teething support. Later weeks emphasize structured routines, stronger obedience, recall, behavior shaping, grooming, and building confidence. Common challenges include potty setbacks, mouthing, sleep disruptions, fear periods, and separation concerns. Consistency, patience, positive reinforcement, health monitoring, and guided exploration ensure a smooth, healthy start.