The phrase 'Step Up to the Plate' means to accept a challenge or responsibility for something; to rise to the occasion.
Example of Use: "It's time for Tom to step up to the plate and take on his share of work."
You probably won’t be surprised to learn that the origin of the idiom 'step up to the plate' is baseball. No one is certain when the term was first used as an idiom, but the expression is a very easy one to understand. When a baseball player is prepared to receive a pitch, he or she 'steps up to the plate' to indicate readiness.