OpenJDK is basically a source only project (though they do release reference binaries for the first six months, which usually results in three releases, e.g. 17.0.0 - 17.0.2). After those three months, newer releases are only available through the vendors (e.g. for Java 17.0.5). All those listed are variants of OpenJDK 17 (except IBM Semeru, which is OpenJ9, which itself is a variant of OpenJDK). And bar vendor specific extras, or optional features like garbage collectors, they are basically the same, and have been tested for compliance with the Java specification.

In the Java world, you pick a vendor, and use its binaries instead of the binaries from OpenJDK itself (which generally don't go further then x.0.2, while vendor specific versions continue to receive updates if they are LTS versions). Personally, I usually use Eclipse Temurin builds.

Java doesn't mind if you install multiple versions. This is often required; java is not backwards compatible (it tries to change little, but e.g. the java8 to java9 transition broke a ton of stuff, much of it needless and much of it not reasonably expectable or fixable by libraries and apps, so a bunch of java apps and libraries only run on java8 - just an example).

So, yes, you have installed JDK17. Also, yes, if you just run java without specifying which one you want, you so happen to get java13 here.

To see all installed javas, you can run:

Copy/usr/libexec/java_home -V

to 'override', you can use something like (depends on which shell you're using on your mac):

Copyexport JAVA_HOME=`/usr/libexec/java_home -v 17`

(the backticks mean: Run this then take the output of it and treat that as the 'value' of the expression. here, assign it to the JAVA_HOME env var. -v 17 requests a path to java 17. The -V option lists all and is meant for your eyeballs, not for scripts. The -v option is mostly for scripting, and that's how we're using it here).

JAVA_HOME decides which java is used by some things, but the java you get when you just type java is /usr/bin/java, and that executable is actually just a wrapper that picks a java to run from amongst all installed versions. It uses JAVA_HOME to decide which java to actually run. There are wrappers for all the common commands (javac, too). You can always run e.g. which javac to see what that actually runs; you probably see /usr/bin/javac. Everything in /usr/bin is one of these wrapper thingies that looks at JAVA_HOME and then runs the binary it finds there.