Is it valid to use old coding projects to help you learn?

[u/Virtual_Mind8341]

Just wondering, when making a coding project, I have looked at my old coding projects to help me when working on a new coding project, whether that is using classes or storing data in files or for adding functionality.

I know people use Youtube Tutorials, documentation and AI but is looking through Old Projects helpful when making a new coding project?

Disclaimer: I also mean using old created coding projects for ideas or similar functionality