Ruth and Boaz will begin a family that will become a Royal dynasty, that will include David and ultimately, God's own Son, Jesus Christ. But first, our main actor, Ruth has to do something about it. God puts her into the right place. She just happens to begin to glean in a field owned by her kinsman, Boaz, but divine providence isn't all that's required. She has to do her bit.
Human responsibility is there as well.
If you like, God buts Boaz by the bus stop, but Ruth has to find a way to get herself under the umbrella. There's no doubt as you read through this narrative, that the author wants us to understand that in everything that happens, God is at work. Naomi sees this clearly from the start. God has provided food for his people again. She calls herself Mara, bitter, because of what the Lord has done to her.