The Yawning Gap (The Wanderers Cycle Book 1)

https://www.amazon.com/dp/B0C5YVHWG7
Invisible boundaries have isolated Cor's village for centuries. He accidentally finds a way out.

What he finds outside is a violent and blighted world in decline. He learns that the entire world has been fragmented by similar boundaries, which are leeching their power from life itself. Unless something is done about the boundaries, what's left of life will come to an end.

That heavy task falls on Cor's shoulders. Fortunately, he soon finds friends and fellow wanderers willing to share the load. Together, they venture across their small, fragmented world into the vast unknown beyond the boundaries.

What they find there threatens their world ... but also just might save it.