Prayer is talking to God out loud or in your thoughts. Prayer includes praise to God, confession of sin, asking for your daily needs, and praying for the needs of others.
"But you, when you pray, go into your room, and when you have shut your door, pray to your Father who is in the secret place; and your Father who sees in secret will reward you openly." Matthew 6:6
Jesus taught us the model prayer, called the "Lord's Prayer".
"Our Father in heaven, Hallowed be thy name. Your kingdom come, Your will be done. On Earth as it is in heaven. Give us this day our daily bread. And forgive us our debts, As we forgive our debtors. And do not lead us into temptation, But deliver us from the evil one. For yours is the kingdom and the power and the glory forever. Amen." Matthew 6:9-13