Well I am no apologist but I will let God, in the person of Jesus Christ, speak for Himself
Matthew Chapter 6:
5 "And when you pray, you must not be like the hypocrites; for they love to stand and pray in the synagogues and at the street corners, that they may be seen by men. Truly, I say to you, they have received their reward. 6 But when you pray, go into your room and shut the door and pray to your Father who is in secret; and your Father who sees in secret will reward you. 7 "And in praying do not heap up empty phrases as the Gentiles do; for they think that they will be heard for their many words. 8 Do not be like them, for your Father knows what you need before you ask him.
9 Pray then like this: Our Father who art in heaven, Hallowed be thy name. 10 Thy kingdom come. Thy will be done, On earth as it is in heaven. 11 Give us this day our daily bread; 12 And forgive us our debts, As we also have forgiven our debtors; 13 And lead us not into temptation, But deliver us from evil. 14 For if you forgive men their trespasses, your heavenly Father also will forgive you; 15 but if you do not forgive men their trespasses, neither will your Father forgive your trespasses.
Note above that Jesus, who is the Son of God, and God Himself tells us to pray and He tells us how to pray. He does not say - “Don’t pray because you can’t change God’s mind”. He says TO pray and to Pray quietly (in your room) and humbly for Gods Will and not ours to be done.
Add to this, the fact that the Gospels record several instances of Jesus praying and/or going off to pray, Mt 14:23; Mt 19:13; Mt 26:36: Luke 6:12; Luke 9:28; John 14:26;
The entire Chapter of John 17 is a prayer by Jesus to the Father.
So - We pray because we are commanded and commended to Pray.
We Pray because it strengthens us to Pray.
We Pray because Christ Himself Prayed and we seek to imitate our Lord.
We Pray to place ourselves in God’s Holy presence, opening up to Him ourselves and our desires.
We Pray to better understand God’s Will in our Lives.
We Pray that we may Learn
We Pray that we might grow closer to God in Love.
For all these reasons we pray.
I hope this helps some.
Peace
James