This is the file I originally got.
Where do I find this file '19.3.0.0_64_bit_Installation_Tools_Win.zip'?
Release : 15.8
Unable to find the Oracle_Configuration19.3.0.0_64_bit_Installation_Tools_Win.zip file for completing the Oracle installation
Download the 15.8 Product zip file from support portal
Extract the DLP Software package "DLP_15.8_Platform_Win-IN_15.8.00000.19012.zip" and reach to the below mentioned path from the unzipped location.
You should find the Oracle Configuration zip file in
"DLP_15.8_Platform_Win-IN_15.8.00000.19012\15.8\New_Installs\Oracle_Configuration19.3.0.0_64_bit_Installation_Tools_Win.zip" .
Follow the below document on page 9 which will tell you from where you can get the 19.3.0.0_64_bit_Installation_Tools_Windows.zip file/.
You should get that from the support download page.