Tableau Prep is an ETL tool (Extract, Transform, and Load) that is used to cleanse large amounts of data, to enable them to be used by data scientists and analysts to harness insights.
Whereas, Tableau Desktop is a data visualization tool that is used to create interactively and attractive dashboards, from the cleansed data that has gone through Tableau prep.
Both tools serve different purposes. If you wish now to get started with Tableau, then check out the Tableau tutorial, and if you are aiming to get certified in Tableau, then check out the Tableau certification course. This course helps you in understanding from basic to advanced level from industry experts.
Also, check out our YouTube video to get your fundamentals correct on Tableau.