OK, granted, you may say. But what I do with that material is my own choice. And indeed it is, from one perspective. From the human, in-the-flow-of-time perspective, whatever you do that was not forced upon you was done freely, by your own choice. The Bible recognizes and assumes the reality of this choice. Joshua told the Israelites, "Choose this day whom you will serve...as for me and my house, we will serve the Lord." God definitely calls us to choose, and respects those choices.
Nevertheless, there is an out-of-the-flow-of-time, eternal perspective that belongs only to God and is the realm of His own will. We cannot comprehend this, as we cannot move our own minds out of temporal ways of thoughts. We live in time as fish live in water, or, more precisely, as we live in the three dimensions of space. Though we can mathematically describe additional dimensions, we cannot perceive them, we cannot hold them in our mind's eye in the way that we can recall or imagine a smell, a landscape, or a conversation. We live in time and space, and probably always will (presuming that our resurrected existence will be like it was before the Fall, wherein Adam lived in time and space.) So we can recognize and talk about the eternal will of God, and say true things about it, but we cannot fully comprehend it, and in fact all we can know about it is what is revealed to us by one who lives in it, namely God.
Paul opens the letter to the Ephesians by noting that he is an apostle "by the will of God." The full story is told in Acts. Paul, being born into a prominent Jewish family and into Roman citizenship with all its privileges, received an education from Gamaliel, a rabbi who is still famous and whose writings are still studied today. Paul was a persecutor of the followers of Jesus. In fact, Jesus himself states that Paul was a persecutor of Jesus! Keep in mind that, from our Western perspective, this was all Paul's own choice. Paul became an apostle of Jesus because Jesus forcibly knocked him from his horse and blinded him while he was on his way to arrest Christians in Damascus. Paul was told to go into Damascus, blind, and wait for further instructions. So when Paul states that he is an apostle "by the will of God", he knows that quite literally, and forcibly, and through no choice of his own, his course in life was redirected 180 degrees, and from being a persecutor of Jesus and Christians he would become himself a persecuted Christian and "doulos" (bondservant/slave) of Christ. This was not because Paul chose this way after much consideration and reflection, but because God chose him and forcibly intervened in his life, against Paul's will.
This perspective of Paul, that what he is, he is by the will of God, is key to understanding much of the rest that he will write to the Ephesians.
But consider: what are you "by the will of God"? Are you a wife, a mother, a husband, a father? Do you really see these as being "by the will of God"? If so, then you will see that you are called to those roles, that they were assigned to you by your maker. Were you given a strong body? a capable mind? If so, you were assigned those resources by your Father. Were you given a broken body or mind? If so, then no less than the able-bodied, you have been given these limitations for a purpose, and you are who you are "by the will of God". Let us think first about what we have been given, and only then about what we "will" do.