How were the andees mountain range and the Himalayas formed differently?

Answer 1

They are both the result of plate tectonics. The Andes mountains are the result of plate tectonics when the so-called South American plate was forced upwards by two other plates covered by oceans that drifted under and into it.

The Himalayas formed when the Indian subcontinent drifted northwards and finally bumped into South Asia. The enormous mass of the Indian continent meant that on contact this drift did not immediately stop, but India kept forcing itself nothwards, forcing the earth before it up and 'folding' it into mountains. To this day this drift continues, at a pace of almost 7 centimeters a year.