Landscaping and Waterscaping tools in Animal Crossing: New Horizons are unavailable from the start and require a little grinding before you can unlock them. Once these tools are unlocked, you will get the ability to terraform your Island.
To unlock the Landscaping, your first task is to get the “Resident Services building,” which requires 5 villagers. After this, build a campsite and ensure you get 10 or more villagers. Visiting the Islands can help you get villagers.
With these out of the way, you must improve your Island rating to 3 stars. To get this rating, you need to do many tasks, including building houses, decorating your Island with different items, placing fencings, and Planting Flowers.
After these tasks and getting a 3-star rating, K.K. Slider will visit your Island and perform. This will unlock the Island Designer App that allows you to do terraforming and Request Cleanup. Now, all you need to do to unlock the Landscaping and Waterscaping tools in Animal Crossing New Horizons is visit the Nook Stop terminal.
From the Nook Stop terminal, you can redeem landscaping and waterscaping permits by spending 6,000 Nook Miles. This will give you access to landscaping and waterscaping tools on your island in ACNH. Other tools are available at the Nook Stop, but you don’t need them to change your Island’s landscape.