Here you can find the latest server build available for Space Station 14.
The latest build is from Tuesday, 27 February 2024 at 13:59 UTC. Pick whatever build suits the operating system you're trying to host on:
The version is a9502be29e100edfa4d52aabf8dcaccb45f06c62
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.