This is from the USCCB:
Let us offer a reminder on the Church’s fasting and abstinence teachings:
Ash Wednesday and Good Friday are obligatory days of universal fast and abstinence. Fasting is obligatory for all who have completed their 18th year and have not yet reached their 60th year. Fasting allows a person to eat one full meal. Two smaller meals may be taken, not to equal one full meal. Abstinence (from meat) is obligatory for all who have reached their 14th year.
If possible, the fast on Good Friday is continued until the Easter Vigil (on Holy Saturday night) as the “paschal fast” to honor the suffering and death of the Lord Jesus, and to prepare ourselves to share more fully and to celebrate more readily his Resurrection.
Fridays in Lent are obligatory days of complete abstinence (from meat) for all who have completed their 14th year.
We encourage you to make use of the site. Through our works of prayer, fasting, and abstinence, let us heed the prophet Joel’s exhortation to return to God with our whole heart (2:12). Source]
Not only is Good Friday a day of abstinence, it is one of the two days of the year when we are required to fast. And the Triduum is a most sacred time when we are encouraged to continue to fast.