open your wrapper.conf file (C:\SonarQube\conf\wrapper.conf), it has default:
# Path to JVM executable. By default it must be available in PATH. # Can be an absolute path, for example: #wrapper.java.command=/path/to/my/jdk/bin/java wrapper.java.command=java
change it to (i have jdk12, you can adjust it)
# Path to JVM executable. By default it must be available in PATH. # Can be an absolute path, for example: #wrapper.java.command=/path/to/my/jdk/bin/java #wrapper.java.command=java wrapper.java.command=C:\Program Files\Java\jdk-12.0.2\bin\java
save, run C:\SonarQube\bin\windows-x86-64\StartSonar.bat to start SonarQube