Hello Mohan,
Are you asking how to create an SSL certificate or where to reference the certificate (server.xml). This is an excellent reference. Running Jira applications over SSL or HTTPS | Administering Jira applications Data Center and Server 8.22 | Atlassian Documentation
Hello Mohan,
If you are looking for how to convert an SSL certificate in a .pfx format to a .jks format then this link will be of good help to you.
https://www.digicert.com/kb/ssl-support/jks-import-export-java.htm