This is where the settings for the Java runtime live, like the location of the runtime and any Java arguments to use. For information about how to get a correct Java version, see: Using-the-right-Java ...

Of course MultiMC can not detect Mojangs java (but it might be worth checking - many people that use MultiMC have Mojangs official launcher, this would make MultiMC much more userfriendly). But it ...