Custom XML Feed file

I am having a job site in wordpress and want to add my jobs at jobs.trovit.co.za via rss feed but trovit require custom xml feed file. Trovit has given instructions for custom xml file at https://about.trovit.com/your-ads-on-trovit/southafrica/feed-za-jobs/

But I cannot understand how to make this custom xml file in wordpress so can any one help to create this custom xml file?