Free, quarterly builds of OpenJDK for Linux, Windows, and MacOS.
This website allows you to download various versions of JDK and JRE, but not version 19.
You can creating a Custom JRE from a JDK using jlink.exe:
jlink is a tool built into the JDK that is specifically designed to generate a custom Java runtime image.
It allows you to create a tailored JRE that contains only the modules required by your application, resulting in a smaller and more efficient runtime environment.