Minecraft wiki entry for Setting_up_a_server, associated text: Windows
How to make a Minecraft Server in under 10 Minutes! (Port Forward Guide Too!)
How to Make a Minecraft Server in 2020 (1.15.2) | 5:43 Pt. 2 - Easy: Port Forward | 3:11
How to create a Minecraft Server in 2020 tutorial
Mac OS X
How to SET UP MINECRAFT SERVER on Mac OS
Port Forward (easy method)
Alternative video tutorial on setting up a Minecraft server with Mac
Linux
Linux tutorial for more advanced users
How to Install Minecraft Server on CentOS
How to make a Minecraft Server on Ubuntu for beginners
Others
How to Set Up Port Forwarding
How to Port Forward any Minecraft Server (1.6.2)
Alternative port forwarding tutorial for Windows (with pictures)
Full course
Course: How to Make a Server