This is the 9545th most frequent Russian word.
финберга
It seems "финберга" does not have a direct meaning in Russian; it may be a proper noun, misspelling, or a rare term.
Here, 'финберга' is used as a proper noun denoting the name of an individual who was a teacher.
Финберга был моим учителем в старшей школе.
Finberga was my teacher in high school.
In this context, 'финберга' is again used as a proper noun to reference a specific person during a conversation.
Я спросил Финберга о домашнем задании, но он был занят.
I asked Finberga about the homework, but he was busy.
Here, 'финберга' is used to denote the name of a place (a lake), contextualized by the geographical reference.