How many years in prison must a person serve for first degree murder 23 years sentence?

In most jurisdictions, a first-degree murder sentence of 23 years typically means that the individual must serve a significant portion of that time before being eligible for parole. However, specific laws vary by state or country regarding parole eligibility, good behavior credits, and mandatory minimums. In some places, the person could serve around 85% of the sentence before being considered for parole. It's important to consult local laws for exact details.