feel one's oats

/F IY1 L W AH0 N EH0 S OW0 T S/
verb
  1. 1

    To feel energetic or frisky; to behave in a vigorous or bold manner.

  2. 2

    To feel important; to be empowered.

Source: https://en.wiktionary.org/wiki/feel%20one's%20oats