You will find your Java installations at
C:\Program Files\Java\
You can install different versions at the same time
The run bat usually uses the latest build
So if you are using 1.20.1 (which requires Java 17), set the path to the Java 17 installation in your script
For example:
"C:\Program Files\Java\jdk-17.0.9\bin\javaw.exe" -Xmx4G -Xms2048M -jar server.jar
pause
Just make sure you are using the correct Java version for the Minecraft version you are using
Use the exact path to the javaw.exe and keep the quotation marks