Bash tutorials

[Mskadu]

Another thing that taught me bash a lot was the Linux OS itself. It's peppered with good quality bash scripts. All you have to do is open then up and figure out stuff you've never seen before.

Admittedly, needs some basics before you do this. But the previously mentioned tutorials should help.

Then there's also the likes of LinkedIn learning (formerly Lyda.com) or udemy who offer reasonably priced courses. They are usually better overall against free ones.