So first of all, the server will only be accessible in the network you run it in (=at your home) unless you use something like hamachi or run the server on a rootserver / vps.
- Download the server files for SkyFactory 4 Server and unzip the file
- Run Install.bat and wait for it to finish
- Run ServerStart.bat and wait for it to close
- Open the eula.txt and set eula=false to eula=true (you agree to the Minecraft EULA by doing this)
- Now you can run the server by running ServerStart.bat
You can now join the server over the IP of the computer it is running on.