Due to Adam's sin, we all come into this world as fallen sinners. Our heart is corrupt and we are incapable of pleasing God in anyway. Why? Because our heart is not right! We are at enmity with God! As such, we are unable to please God.
Are we provided a will, free will, to make the decisions that we make? I believe that we are! However, the will is not sovereign above all things. It can only will to do things based on our heart's desire. Therefore, I may look up, look down, turn right, go on vacation, etc.. because my heart desires that I do so. Can I turn to God or please Him in any way? No! Why? Because our heart is not right! We are conceived in sin, children of wrath, incapable of saving good, prone to evil, and without the regenerating grace of the Holy Spirit, are neither able or willing to turn to God.
So the question is, How do I get a new heart? Is it the natural heart's desire to turn to God? NO, and it never will be unless God call us to Him.
Most often the call takes place through hearing or reading God's word. It is not the fault of the gospel, nor of Christ offered therein, nor God, who calls men by the gospel that some refuse to come and be converted. The fault lies in themselves; some of whom reject the Word; others, thought they receive it, it makes no lasting impression on their heart. But some hear and obey. This our Savior teaches in the parable of the sower.
The fact that they hear and respond must be wholly ascribed to God, who, as He has chosen His own from eternity in Christ, so He calls them effectually in time, confers upon them faith and repentance, and rescues them from the power of darkness. The Spirit softens the hardened heart, and infuses new qualities into the will, which, though before was dead. Now we, like a good tree may bring forth the fruits of good actions. However, these good actions play no part in our salvation.
This act was not of ourselves, but a work of God only. No man may boast, it is a gift to God's chosen people.
What happens to those who do not respond to this gift? They are not God's elect. [John 10:27] My sheep hear my voice, and I know them, and they follow me. God is under no obligation to confer this grace upon any! No, how can He be indebted to one who has nothing of his own but sin and falsehood?
The manner of this operation cannot be fully comprehended by believers in this life. Nevertheless, they are satisfied to know and experience that by the grace of God they are enabled to believe with the heart and to love their Savior. At this time, We see through the glass dimly.