earth

I'm happy to give that advice.

Humanity can continue to operate warm the planet until it is inhospitable to industrial civilisation, but life will continue beyond that (so we're not in danger of going full Venus).

We are currently at 420 ppm carbon dioxide or so. About 50 million years ago, the level was about 1500 ppm.

The climate would also have become much wetter, with the increase in evaporation rates peaking in the tropics. Deuterium isotopes reveal that much more of this moisture was transported polewards than normal.[52] Warm weather would have predominated as far north as the Polar basin. Finds of fossils of Azolla floating ferns in polar regions indicate subtropic temperatures at the poles.[53] Central China during the PETM hosted dense subtropical forests as a result of the significant increase in rates of precipitation in the region, with average temperatures between 21 °C and 24 °C and mean annual precipitation ranging from 1,396 to 1,997 mm.[54] Very high precipitation is also evidenced in the Cambay Shale Formation of India by the deposition of thick lignitic seams as a consequence of increased soil erosion and organic matter burial.

A study published in May 2021 concluded that fish thrived in at least some tropical areas during the PETM, based on discovered fish fossils including Mene maculata at Ras Gharib, Egypt

Many major mammalian clades – including hyaenodontids, artiodactyls, perissodactyls, and primates – appeared and spread around the globe 13,000 to 22,000 years after the initiation of the PETM

The diversity of insect herbivory, as measured by the amount and diversity of damage to plants caused by insects, increased during the PETM in correlation with global warming.[125] The ant genus Gesomyrmex radiated across Eurasia during the PETM.[126] As with mammals, soil-dwelling invertebrates are observed to have dwarfed during the PETM.[127]

This is after mass extinctions of course, but life will continue for at least a few hundred million years yet