Any Red Hat Certification really needs enough time of preparation specially if you find it really hard and difficult. We highly recommended to take the official courses for it will provide you not only official material but also an environment that is properly setup for best user experience.
RHCE is a real challenge, the reason for this is that other exams have so far expected scopes which is not the case in RHCE, for RHCE you need prepare for it, and you must have a real experience in different areas and protocols, I failed RHCE once, and I had to redo it one year later, bottom line you should not limit your experience to the training document, but you need to practice a lot, finally one important hint, keep an eye on the exam prequisites in red hat web site, make sure you practiced all of them prior going to the exam.
Careful here. "Easy" is subjective.
As a Red Hat Certified Examiner, I've delivered EX300 over the years, and seen many students struggle. We don't publish success/failures for the exam but my observation is that I would not classify it as an easy exam.
It's a real hands on test of your knowledge. There's no multiple guessing your way through it. There are lots of pages linked aready that tell you what the exam covers. When you know that material backwards and forwards then you're ready. You need hands on experience, just reading is not enough.
When I took the exam, we had one examinee walk out in the first 5 minutes because they discovered they weren't ready.
Consider the book