“Using foresight” and “fearing the future” are two vastly different things. One is not the extreme of the other, but the opposite. The more foresight we use, the less fear (foreboding) we have. The more we are tortured by anxious thoughts about a POSSIBLE future, the less clear vision we have of a LIKELY future … and the less power to influence it.
So when Jesus teaches in Matthew 6:24-25 not to be anxious, He does not mean to prevent the exercise of wise foresight but the constant preoccupation and distraction of the heart looking forward and fearing.