Download the certificate from the web browser and install it using keytools.
Click on "Connection is secure"
Click on export and save it to your hard disk
Open CMD and type below command.
keytool -import -alias ANY_NAME_YOU_WANT_TO_GIVE -file PATH_TO_YOUR_CERTIFICATE -keystore PATH_OF_JAVA_KEYSTORE
PATH_OF_JAVA_KEYSTORE - file will be available at C:\Program Files\Amazon Corretto\jdk11.0.20_9\lib\security
If the keytools are not recognize as a valid command, add java/bin folder to your system environment variable paths.