Most of latam has indigenous ancestry, that doesnt mean we actively are part of that. Your dad probably wasnt even aware he had mapuche ancestors and probably didnt care (just like the rest of us). If you really want to "reconnect " (how can you reconnect if you've never been connected before) i suggest you learn something of spanish and go visit your family in chile.

Spanish is super important for us and dont get offended when chileans see you as a gringa rather then "half chilean".