How to build software that is actually useful?

So I'm a self taught developer, after 2 years of learning to code and picking up the basics of Laravel and VueJs I recently landed a job as a junior Web Developer at a Marketing agency. These past 3 weeks I've been doing basically grunt work mostly and CRUD. I want to know how to push my skills beyond CRUD. What this job has given me so far is perspective, seeing what its like to build software for real clients in the real world. How can I better understand layers of abstraction and build feature that are actually useful? Any books I should read or anything specific is should build?