In all honesty, the web's awash with good-quality scripting tutorials. Bash is the most common general-purpose scripting language you'll encounter on your travels through the Linux universe, so it's one of the best to begin with. Most examples online tend to use Bash anyway, so it's a good one to have in your Linux "toolbox".
In my experience, scripting is not really a skill you can learn by undertaking a 'course'. I.e., you start off, green as grass, and 6 months/a year later you 'graduate' as an expert. It doesn't really work like that; well, it didn't for me, anyway.
I developed my own Bash skills, meagre as they are, over a period of time. Of course, it's not like I was trying to train for a position like a sysadmin, say.....for me, it's totally a hobby, so I've picked up a snippet here, an example there; tried things out, practised with examples, tweaked, titivated, tried again.....and again.....and again. Practice definitely makes perfect, and it's astonishing how many times you'll find yourself using, and re-using, the same code snippets (or modifications thereof.)
It's like most languages; once you've grasped the basics, you can build the most fantastically complex scripts from nothing; usually, little by little, testing each line - or "phrase" - as you go. And always:- Practice, practice, practice. In no time at all, you'll find yourself starting to write wee scripts to automate stuff, and make life easier for yourself at every turn.
THIS isn't a bad place to start.
I'll say this; degree of success depends to a large extent on degree of interest. The more interested you are at learning this stuff, the more quickly you'll pick it up.....because it's something you WANT to do. Not something you feel you HAVE to do.....
Mike. 