Download the jar, put in plugins folder, run the server and wait till started. Then stop. Go to the plugins folder and CropXP, under it you should find the config file to then add combination of the following:
POTATOES, CARROTS, COCOA, BEETROOTS, WHEAT, MELON, PUMPKIN, NETHER_WART. More spigot crops can be added but for compatibility the list only includes those from 1.17.