Hebrews 5:7 who, in the days of His flesh, when He had offered up prayers and supplications, with vehement cries and tears to Him who was able to save Him from death, and was heard because of His godly fear
Have you noticed how Jesus acted towards God the Father? Have you stopped to think about the example He set down for us?
Jesus is the Son of God and yet He would still kneel before God and offer up cries and prayers. God does not need to know what was going on, but He needs to know we know our hearts.
When we cry to God it is us opening up our hearts to God. When we pray it is us making known our wants and needs.
When God answers we then get to see how much He cares because He answers our deepest needs openly.