Either import the schematic into a world of your choise or use the world provided with it already implemented

After you break the lever on the bedrock cube the border will be set, and will shrink during the night, and grow during the day, growing more each day then it shrinks each night slowly giving you more of your world to use, the border will tick damage on you if you are outside it, on the first night the border will be tiny (50 blocks each way i believe) just a warning

GL HF leme know how it is coooos i havnt tried it myself~