Free choice or free will happens when the provider of the choice will not punish the other for choosing one of these choices.
In other words God is not going to punish us when he gives us free choice. However, we will face all the natural consequences of our choice.
For example, God has provided us with fire and we have choices here. We could use it to cook food, keep us warm or keep wild animal away.
We could also use this to destroy ourselves with it. God gives us choice and though he will not punish but he allows its natural consequence to happen. These consequences many be desirable or catastrophic. It depends on our choices. What is the point of having a choice when we cannot have its natural consequence.
Yes, your are right, we have the right to choose.
Now about God 's Will. There is a lot of misconception about it.
Many believe that God's Will is the reason for their unanswered prayers. This is not true. This is too complex to be discussed here. If there is any hint, it has to do with the lack of faith in God's power.
Actually, the good news about God's Will is that your Will is his Will. If you have faith of a mustard seed, your Will will be his Will. However, just as many truths about God, many will discard as this as too good to believe.
If God Wills something it will definitely happen with or without our choice. There is simply no choice to choose.