How long would it take for Earth's average temperature to be 100 degrees

If we continue trashing the planet, would Earth's temperature rise?

given that the earth's average temperature is well below 100 degrees fahrenheit (im assuming you mean fahrenheit as 100 celsius is boiling), it would take a long time. Global warming has only warmed the planet 1.33 degrees Fahrenheit in the past century (citation: https://www2.ucar.edu/climate/faq/how-mu…
Not even the models that show the most aggressive global warming show anything near a 100 degree average anytime soon (and by soon i mean like in the next 100 years or so).
it will never reach 100 degrees by anthropogenic global warming. It was not even 100 degree average during the dinosaur days, when there was no permanent ice at the poles , the earth was several degrees warmer than today, and the carbon dioxide concentration was several times higher.

The other answerer is spot on. I just want to add that change is a part of the earth. The climate has changed multiple times during the planet's history. In other words, change would occur whether humans were here or not. The only question is whether humans are having an impact, and if so, how much of an impact.

It is these repeated atmospheric and geological upheavals that have formed the earth as we know it.
It is rather arrogant to believe that the earth ceased to evolve and change, just because a species called Homo sapien appeared.