How to install Minecraft Server on Raspberry Pi 4

Basic File System Setup.

Change Directory to Desktop

 cd home/pi/Desktop  or cd Desktop    

Make a new directory called minecraft_server

 mkdir minecraft_Server 
 Change to the directory
 cd minecraft_server   

Use the touch command to create a shell script file in that directory name Start.sh

 touch start.sh

Modify the start.sh file using nano.

sudo nano start.sh

Add the following 2 lines and save file:

 cd /home/pi/Desktop/minecraft_server/
 java -Xmx1024M -Xmx2000M -XX:+UseConcMarkSweepGC -jar spigot.jar nogui

 cd Documents - Change to Documents Directory
 cd home/pi - Change to pi Directory
 cd .. -  Return one level up 
 cd / - Change to root Directory 

pwd - Print Working Directory Absolute Path

mkdir - Make directory

 mkdir rusty - Creates a directory named rusty
 mkdir Documents/rusty - Creates a directory named rusty in the folder Documents.