As you may have already discovered, there is no such thing as a simple, cheap chainsaw course. I researched it fairly intensively a few year ago when a landowner wanted to see a qualification before I cut logs on her land. Even a two day course was in the region of £600, and covered loads of things I (and you) probably already knew – how to use the chain brake, how to mix fuel etc.
I decided that my money would be far better spent on a load of high end PPE (I never start the saw without boots, trousers, gloves, helmet with visor and ear defenders) and some safety gear – I use one of those saw horses which clamps the chainsaw bar whenever I can.
You can have all the training and tickets going, and still make silly mistakes – perhaps using a saw every day makes you ambivalent to the risks? Both pro tree surgeons I know have running chain injuries to hands and arms. Just treat the saw as a live creature liable to leap up at you at any moment and you should be safe enough.