If you are a developing developer:
ThisAPI is simple and easy to use. First of all, download and import the plugin into your project and run it along with your file.
kliman4ch ThisAPI:
An easy-to-use API that allows developers to use various functions in Minecraft with long lines of code.
At the moment, the plugin is provided for game version 1.12
Messages:
Displaying a message to all players on the server:
ThisAPI.adminMessageAll ("Subtitle", "Message");
Chat output: [Subtitle] Message
Displaying a message to a specific player on the server:
ThisAPI.adminMessageToPlayer ("Subtitle", "Message", player);
Chat output: [Subtitle] Message