From next time write the code yourself and minimize the copy/pasting habit as much as you can. Using a good IDE helps control the copy/pasting habit to some extent.

Start here, follow the topics you have not tried yet: http://www.tuxradar.com/practicalphp

What's the best way to learn all the stuff I missed by not going to school?

how can I get a job that is asking for engineers to apply?

You need skills that those engineers have.

You don't need to go to school to master the data structures and algorithms, for reference there are bunch of university resources available, and there are lot of implemented code for us to checkout. Refer links others have suggested here. Give some time to learn these advance topics.

Edit: added few lines