Plants make their own food through a process called photosynthesis. Here's how it works:

1. Plants absorb sunlight using a green pigment in their leaves called chlorophyll.

2. At the same time, the plant's roots absorb water from the soil.

3. The plant also takes in carbon dioxide from the air through tiny holes in the leaves called stomata.

4. Inside the leaves, the chloroplasts (which contain chlorophyll) use the absorbed light energy to convert water and carbon dioxide into glucose, a type of sugar that acts as the plant's food.

5. The plant uses this glucose for energy and growth, and it releases oxygen as a byproduct, which is released back into the atmosphere through the stomata.

So, plants basically use sunlight, water, and carbon dioxide to create their own food (glucose) and release oxygen in the process. This is why plants are so important for life on Earth – they provide food for many living things and release the oxygen we need to breathe.