In S.W. Europe, one has to live on fresh air! (6)
I believe the answer is:
iberia
'in s w europe' is the definition.
I can't tell whether this definition defines the answer.
'one has to live on fresh air' is the wordplay.
'one' becomes 'i' (Roman numeral).
'has' is a charade indicator (letters next to each other).
'to live' becomes 'be' (synonyms).
'on' means one lot of letters goes inside another.
'fresh' indicates an anagram (a fresh re-ordering of the letters).
'air' is an anagram of 'ria'.
'be' going inside 'ria' is 'beria'.
'i'+'beria'='IBERIA'
Can you help me to learn more?
(Other definitions for iberia that I've seen before include "Spain's national flag-carrying airline" , "Where Juan possibly lives" , "Spain and Portugal - airline" , "Great European peninsula containing Spain and Portugal" , "Overpower, overwhelm" .)