The support for M1 is backported at least by Azul, so you can get a Java 8 version which works on a M1

https://www.azul.com/downloads/?version=java-8-lts&os=macos&...

It's worth noting that you may not always want to use the ARM JVM on M1 even if it's available, because then anything linked by JNI needs to be running on ARM also.

I'm on an M1 Mac and have spent more time using the x86 JVM because the ARM JVM is less likely to have applications Just Work.