All software fully updated. On Bootcamp is Windows 10, 64bit version, fully updated as well. - I need to install Java on this Windows partition, but fail to do so: ...

If you want to download and install Java JDK 18 on Windows 11/10 computer, you will also have to set up a Path in Environment Variable.

If you run into problems installing Java on Windows 7 or Windows 8, try installing Java as an administrator. To do so, download the offline installer and save it to an empty folder on your hard disk.

If you want to download Java 64-bit or 32-bit on your Windows 11 or Windows 10 computer then follow the method mentioned here.