Yes, Lent is generally the 40 day journey when Jesus didn't drink or eat while he's at the desert.
Lent begins on Ash Wednesday and ends at sundown on Holy Thursday. It's a period of preparation to celebrate the Lord's Resurrection at Easter. During Lent, we seek the Lord in prayer by reading Sacred Scripture; we serve by giving alms; and we practice self-control through fasting. We are called not only to abstain from luxuries during Lent, but to a true inner conversion of heart as we seek to follow Christ's will more faithfully. We recall the waters of baptism in which we were also baptized into Christ's death, died to sin and evil, and began new life in Christ. (Source: https://www.usccb.org/prayer-worship/liturgical-year/lent)
Abstinence is basically the law which requires everyone that is 14 and above to not eat meat during Fridays. Therefore, We are obliged to eat fish or seafood for the whole Friday during Lent