In relation to the environment: "Natural" can refer to something that occurs in nature, without human intervention or modification. For example, natural resources like water, air, and forests are those that exist in the environment without being created or altered by humans.
In relation to food: "Natural" can also be used to describe food that is minimally processed and free from artificial additives, preservatives, or flavors. This type of food is often considered healthier and more wholesome than heavily processed foods.
In relation to behavior: "Natural" can refer to a behavior or action that feels instinctive or in line with one's natural inclinations. For example, a musician might say that playing an instrument feels natural to them, meaning that it comes easily and intuitively.