What will happen if whole amazon forest get burn
I read some articles recently that the whole thing was portrayed per-dramatically and that this year's fires do not deviate significantly from the perennial average (10 years) and that Amazonia produces not 20 but only 6 percent of the earth's oxygen etc.
Of course, it's still a disaster, but not the cataclysm as some try to prove without concrete or true facts.
I don't think that whole Amazon may disappear but it will happen, we will still survive, don't worry

The temperature will probably increase and the sea level will increase, but it will happen anyway and is happening right now.
I don't know bout the oxygen levels but it's definitely a disaster for biodiversity. There could be species that would die before being discovered.
And I'm not talking about this purely from a conservation viewpoint. We could learn a lot from some species that might be discovered, like medicines etc.