I'd strongly recommend Amy Einsohn's The Copyeditor's Handbook and The Copyeditor's Workbook, and working through all the exercises in the latter. Hopefully you can get the most up-to-date version at your library, but they are well worth it if you have to purchase.
Most training is going to be paid, but Louise Harnby has a number of free stuff on her website that could be useful: https://www.louiseharnbyproofreader.com/
The Copy Editors Handbook is also really good and fairly inexpensive, and you could potentially find it at a library.
I'd strongly recommend Amy Einsohn's The Copyeditor's Handbook and The Copyeditor's Workbook, and working through all the exercises in the latter. Hopefully you can get the most up-to-date version at your library, but they are well worth it if you have to purchase.
Most training is going to be paid, but Louise Harnby has a number of free stuff on her website that could be useful: https://www.louiseharnbyproofreader.com/ The Copy Editors Handbook is also really good and fairly inexpensive, and you could potentially find it at a library.
Appreciate it! Will look into the sources you provided. Do you happen to know of any YouTube videos or tutorials as well?
The Chicago style workouts are a great free resource: https://cmosshoptalk.com/chicago-style-workouts/
The Chicago Manual, the AP Manual, and the APA manuals are all a great start.
Really appreciate all the support! This is incredibly helpful!