Study the basic questions in online and work in desktop and get some practice.
Question will mainly based on issues faced in project and complex situations.
Help in community and workout some issues and get some idea.
Follow the below link and you will get something to start,
Help the community, this is the best way to learn.
Feel free to ping me at any time if you face any issue. If the above two URL helps , mark the answer as correct and start practicing Tableau.
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