Here you can find the latest server build available for Space Station 14.
The latest build is from Friday, 26 April 2024 at 13:20 UTC. Pick whatever build suits the operating system you're trying to host on:
The version is a04d143c2ce4494f25b596edffb2fcf7101d3faa
If you somehow ended up here without reading the Server Hosting Tutorial, go read that first. It tells you how to actually host a server.