You can see the rules ( as in Timatic here ) - https://www.iatatravelcentre.com/world.php

For Chile you need to be 'fully vaccinated' .. this means a full primary course .. they don't require boosters ( where for instance they were required by other countries in the past like Austria, Italy etc. they were explicitly called out in the rules in Timatic .. otherwise if it says 'fully vaccinated' it means primary course completed which is the two doses in most cases )