The Amazon forest is unique in many ways but most importantly because unlike other forests, it CANNOT grow back. The reason for this is that it is a leftover from when the planet was covered in rainforests because it was a lot warmer and wetter in the Eocene epoch. The forest is sustained by the rain it creates from itself. Once the trees are gone, the water will be gone. [1] We also have reasons to think this self-sustaining climate is going to collapse soon [2]
So far the best way to protect it I have found is through the Rainforest Trust [3] which is a foundation that's trying to purchase and protect parts of the rainforests that companies would otherwise cut or burn down for agricultural use.
[1]https://youtu.be/hb3b-A6QAc8
[2]https://www.nasa.gov/earth-and-climate/human-activities-are-...