All living being (or organism, in sciency language) needs nutrients to survive. For some, they get theirs from another living being (like how cow eat plants and snake eat rats). We call this kind of organism heterotroph (from Ancient Greek: héteros means "other" and trophḗ means "nutrition"). The other kind who's able to make their own nutrients from nonliving being are called autotroph (in Ancient Greek, auto means "self"), like plants, algae, and many kind of bacteria. In food chain, we call autotrophic organism as producer, and heterotroph as consumer.

Now, how are plants able to make their own "food"? Surely they can't grills, bakes, or even boils, right? They have their own unique process, called photosynthesis (from the Greek: phōs means "light", and sunthesis; "putting together").

Basically, they use water (H₂O) and carbon dioxide (CO₂) as ingredients, and using the energy from sunlight, they convert those into sugar (more specifically carbohydrates: C₆H₁₂O₆) as energy source in form of chemical energy, and oxygen (O₂) as a waste product (Don't get me wrong, plants will also use the oxygen in their respiration process). This whole photosynthesis process is really complex, but the simplified version can be written:

Like we already know, every living being consists of cell, like how lego houses consists of lego bricks. These cells also consist of things called organelles that varies in function. In plants, there's a special organelles in their cells called chloroplasts. The photosynthesis process take place in these chloroplast.

Before, I said photosynthesis use energy from sunlight. For plants, they absorb light primarily using a special pigment called chlorophyll (which reside inside the chloroplast).

Although all cells in green part of a plant have chloroplasts, the majority of those are found in specially adapted structures we called, guess it; leaves.

Well, that's should suffice if we're talking middle school curriculum.

Sorry if there's error in the content or writing (I'm really bad at grammar), hope this helps!

*As a whimsical advice, why did you made an account at Brainly Indonesia (brainly.co.id) and not at brainly.com or brainly.in, since you said you can't speak Indonesian?