Question

what will be effect caused if all the greenery on earth gets extinct​

Answer 1

Without trees, formerly forested areas would become drier and more prone to extreme droughts. When rain did come, flooding would be disastrous. Massive erosion would impact oceans, smothering coral reefs and other marine habitats.

Answer 2

If the greenery on the earth gets extinct means there would be no plant if there would be no plant then biotic components can not breath

and forest area will get dried