can i know God's will for my life?

Well, that depends on which "will" you're talking about. Here's a great excerpt from R.C. Sproul's book, Essential Truths of the Christian Faith:

The Will of God
by R. C. Sproul

Doris Day sang a popular song entitled "Que Sera, Sera," "What will be, will be." At first glance this theme communicates a kind of fatalism that is depressing. Islamic theology frequently says of specific events, "It is the will of Allah."

The Bible is deeply concerned about the will of God – His sovereign authority over His creation and everything in it. When we speak about God's will we do so in at least three different ways. The broader concept is known as God's decretive, sovereign, or hidden will. By this, theologians refer to the will of God by which He sovereignly ordains everything that comes to pass. Because God is sovereign and His will can never be frustrated, we can be sure that nothing happens over which He is not in control. He at least must "permit" whatever happens to happen. Yet even when God passively permits things to happen, He chooses to permit them in that He always has the power and right to intervene and prevent the actions and events of this world. Insofar as He lets things happen, He has "willed" them in this certain sense.

Though God's sovereign will is often hidden from us until after it comes to pass, there is one aspect of His will that is plain to us---His preceptive will. Here God reveals His will through His holy law. For example, it is the will of God that we do not steal; that we love our enemies; that we repent; that we be holy. This aspect of God's will is revealed in His Word as well as in our conscience, by which God has written His moral law upon our heart.

His laws, whether they be found in the Scripture or in the heart, are binding. We have no authority to violate this will. We have the power or ability to thwart the preceptive will of God, though never the right to do so. Nor can we excuse ourselves for sinning by saying, "Que sera, sera." It may be God's sovereign or hidden will that we be "permitted" to sin, as he brings His sovereign will to pass even through and by means of the sinful acts of people. God ordained that Jesus be betrayed by the instrument of Judas's treachery. Yet this makes Judas's sin no less evil or treacherous. When God "permits" us to break His preceptive will, it is not to be understood as permission in the moral sense of His granting us a moral right. His permission gives us the power, but not the right to sin.

The third way the Bible speaks of the will of God is with respect to God's will of disposition. This will describes God's attitude. It defines what is pleasing to Him. For example, God takes no delight in the death of the wicked, yet He most surely wills or decrees the death of the wicked. God's ultimate delight is in His own holiness and righteousness. When He judges the world, He delights in the vindication of His own righteousness and justice, yet He is not gleeful in a vindictive sense toward those who receive His judgment. God is pleased when we find our pleasure in obedience. He is sorely displeased when we are disobedient.

Many Christians become preoccupied or even obsessed with finding the "will" of God for their lives. If the will we are seeking is His secret, hidden, or decretive will, then our quest is a fool's errand. The secret counsel of God is His secret. He has not been pleased to make it known to us. Far from being a mark of spirituality,the quest for God's secret will is an unwarranted invasion of God's privacy. God's secret counsel is none of our business. This is partly why the Bible takes such a negative view of fortune-telling, necromancy, and other forms of prohibited practices.

We would be wise to follow the counsel of John Calvin when he said, "When God closes His holy mouth, I will desist from inquiry." The true mark of spirituality is seen in those seeking to know the will of God that is revealed in His preceptive will. It is the godly person who meditates on God's law day and night. While we seek to be "led" by the Holy Spirit, it is vital to remember that the Holy Spirit is primarily leading us into righteousness. We are called to live our lives by every word that proceeds from the mouth of God. It is His revealed will that is our business, indeed, the chief business of our lives.

Summary

1. The three meanings of the will of God:

(a) Sovereign decretive will, the will by which God brings to pass
whatsoever He decrees. This is hidden to us until it happens.

(b) Preceptive will is God's revealed law or commandments, which we have the
power but not the right to break.

(c) Will of disposition describes God's attitude or disposition. It reveals
what is pleasing to Him.

2. God's sovereign "permission" of human sin is not His moral approval.

Chapter 22
pages 67-69
Essentials Truths Of The Christian Faith
R C Sproul