The mod is relatively simple, so this wiki should be simple to follow.

The mod functions by keeping track of previous bed slept in, and if previous bed breaks, it then spawns you at an older bed rather than world spawn.

It has a single config option maximumBedFallbacks which is defaulted to 3 to avoid circular tp'ing with the mod, if you want to have a higher number on your server/modpack/world, then find the bedfallback server config in your config folders.

Fabric utilizes the ForgeConfigAPIPort mod to have the same config we know from Forge/NeoForge, the Fabric mod also requires Fabric API