Server Protection: Complete Guide on How to Secure Your Server

Protecting your Minecraft server is important to prevent your progress from being destroyed and to ensure your players stay safe while playing 
In this case, we will be using the following resources and plugins:
Paper or Spigot software
WorldGuard
FastAsyncWorldEdit or WorldEdit
LuckPerms
AuthMeReloaded or nLogin

Step 1: Login System
As a first step, it is important to set up a login system by following the setup guide provided by the plugin developer. You should install it in the appropriate game mode or in the auth server if you are running a network.

This ensures that players must set a password when joining the server, and only they can access their account using that password.

Step 2: Permissions and Rank System
As a second step, it is important to configure a rank and permissions system (in this case, LuckPerms). You should create moderation ranks and assign the necessary permissions to manage the server, such as teleportation, bans, and punishments.
In addition to moderation ranks, you should properly adjust player permissions and block dangerous commands such as /op, /minecraft:op, /plugins, and /summon to improve your server’s security.

Step 3: Protect Your World
Finally, it is essential to protect important areas of your server such as the spawn, lobby, and other key zones. Using WorldGuard and FAWE allows you to fully protect these areas by selecting the region and using the command /rg define (name).
This will automatically apply protection, which you can later modify using /rg flags (region).

Additional Tips
Disable dangerous gamerules: To prevent malicious players from destroying the world, you can disable TNT explosions using /gamerule tntexplodes false and mob griefing using /gamerule mobGriefing false.

Keep your server updated: Some Minecraft versions may contain security vulnerabilities that can pose a serious risk. Keeping your server updated to the latest available version helps reduce this risk.
Avoid using OP while offline: It is important to remove operator permissions when logging out. If someone gains access to your account, they will not be able to cause damage. It is recommended to manage everything through permissions instead of OP.

Protect your IPs (Network servers): If you run multiple server modes in a network, additional security is required. If a player discovers the IP of one of your backend servers, it can become a security issue. To prevent this, it is recommended to use the BungeeGuard plugin, which connects your servers using a unique token set in your proxy, depending on the software you use (BungeeCord or Velocity).