Are these trainings worth the cost? Has anybody reading this done them / would be able to provide feedback?
Also seconding the need to understand clock domains and metastability, timing constraints, etc.
Also seconding the need to understand clock domains and metastability, timing constraints, etc.
You're looking for (1) probably a first course in the basics of circuits, (2/3) a first- and second-course in "digital design" or "logic design", (4) an operating systems course (emphasizes how this stuff all works with "The real world"), a basic programming class if you don't have one, and some domain-specific stuff such as digital signal processing, graphics, statistics, finance, or whatever else you're trying to do with this thing.
Probably 5-6 good university classes in total. If you could do these classes a la carte, it's probably the fastest way to learn this stuff (skip the gen eds and all other non-degree requirements). Frankly, it's a lot if you have no prior experience, but I'm not sure that's true.