The best way to dive deep into Tableau is to take the plunge!
Read Tableau online help manual, watch Tableau's free live and recorded training videos, get your hands dirty with practical exercises, check out Tableau Public for inspiration and get involved in Tableau community.
This is a good place to start.
Tableau online help: https://onlinehelp.tableau.com/current/pro/desktop/en-us/help.htm
Then check out the free training videos: Tableau Training and Tutorials
These are all you need in my opinion for a deep dive within 2 weeks.
Thanks Ossai for your reply. I was looking for some advanced stuff.
If you are looking for some challenge up to Jedi stuff, then this may just be a good place to dive all in. It starts from beginner to Jedi level.