If you have chosen to install Java from a ZIP file then
Download the ZIP file containing the appropriate version of Java.
Open the ZIP file and extract the contents to a directory of your choosing.
Modify the sytem Path environment variable to include the "bin" folder within the newly installed Java. For example, if you have extracted the zip file to C:\Tools\jdk8u202-b08, then include C:\Tools\jdk8u202-b08\bin in the system Path. If you are updating from a previous version of Java then you may remove the previous version from the path.