You are confused. The filibuster is basically unlimited debate. It is continuing to talk in order to prevent a vote from taking place.
In order to stop a filibuster, 60 senators need to vote to cut off debate. Only then can they proceed to vote on whatever it is they are debating.
I think the "principle of unlimited debate" is over-rated. It is not in the Constitution, only in the arcane rules of the Senate, which could be changed at any time if Senators voted to change them.
When Republicans were in power, they talked about using the "nuclear option" of changing the rules of the Senate to do away with the filibuster, so Democrats couldn't block some legislation and judicial nominees. Now that the Democrats are in power, perhaps they should do the same so that Republicans can't use the filibuster to block things.
What's good for the goose is good for the gander.