Go work for, without loss of generality, Ramit Sethi for a year. Learn how the business of teaching functions at scale. Then make the business that enables the business of teaching.

(You can pick other examples; I picked Ramit because I think he's savvy, because he runs a savvy shop with lots of needs, and because my understanding of many of those needs maps fairly directly with things one could build.)

A variation of this advice: work for Teachable/etc.

A variation of this advice: sell courses for a living on whatever it is that you're an expert in.