New users are adivsed to start with the new users section in the manual. I advise you to go through that.
In class, instead, we will take the deep dive into the DataFrames.jl package with a showcase.
There is a notebook for you here
The Manual is very well done, and lists a bunch of good resources on the landing page.
This tutorial series is very good for the DataFrames.jl package: https://github.com/bkamins/Julia-DataFrames-Tutorial
The julia academy data science tutorial is full of excellent stuff
The Turing Institute's Data Sciences tutorials give a good intro to data structures and machine learning in julia.