For centuries, a classical education would start with The Trivium; Grammar, Logic and Rhetoric. These three courses will comprehensively teach you how to write, think, argue, analyse arguments and persuade others.
You can purchase each individual course separately as well.
Foundations of Writing will teach you how to be a better writer. Impress your peers with the clarity of your essays.
Foundations of Logic will teach you how to be a better thinker. Impress your peers with the clarity of your reasoning.
Foundations of Economics will teach you concepts fundamental to economic analysis from the ground up. If you have no prior background in economics at all, do not worry, it will build up the ideas assuming that you know nothing.
A course on how to research practically anything. Comprehensive guidance on how to conduct qualitative research.