What I ask is please give me a download link of the version of school that I attend.

No such download exists from the official distributor of Notepad++.

You will have to ask your teacher how they configured Notepad++ at school. My guess is that they are using the NppExec plugin to run the external java compiler, and then use Customize Toolbar plugin to add that NppExec script as a button on the toolbar.

For example, I have an NppExec script that I call “Java-CompileAndRun” with the script

NPP_SAVE
cd "$(CURRENT_DIRECTORY)"
"C:\Program Files (x86)\Java\jdk1.8.0_51\bin\javac" $(FILE_NAME)
"C:\Program Files (x86)\Java\jdk1.8.0_51\bin\java" -classpath "$(CURRENT_DIRECTORY)" $(NAME_PART)

This saves the active file, then uses the Java JDK javac to compile, and the java command to run the compiled output

But that’s just a guess as to what they did. As I said, you will have to ask your teacher how they customized Notepad++ (or explore the various configurations and menu entries in the school’s Notepad++ to figure it out for yourself).