I took the exam to become more familiar with testing methods. My job didn’t require any formal QA training, so I always felt like a wasn’t very technical. The exam gave me an introduction to techniques and terms that I might not have learned otherwise. My job paid for the exam, but I spent a lot of time on self-study (probably too much time to be honest).
I used a Udemy Course and a book called Foundations of Software Testing to study. The Udemy course was essential to me passing the exam.
I also used TM Square’s ISTQB cert channel to review testing terms.
I think that the test is an acceptable way to gain familiarity with QA concepts, but you spend more time learning how to pass the test than improving your techniques. I’m glad that I completed the foundation level exam, but I wouldn’t go further unless it was a job requirement.