Someone wanted to learn this too, so Grasp built them a personal learning path.
You can keep exploring this one or create a path like this one shaped around you.
Recommended resources
Module 1
Excel Fundamentals
Module 2
Data Entry and Editing
Module 3
Structuring Your Worksheet
Module 4
Performing Calculations with Formulas
Module 5
Organizing and Printing Data
Module 6
Visualizing Data with Charts
Module 7