Hi there!
Relax, the HCIA is not very difficult, but it may involve a lot of knowledge.
You can find some unofficial instructional videos (such as YouTube) or other people's notes online for reference. HCIA is a starting point, laying a good foundation for you to more easily prepare for the HCIP and even the HCIE exams, which will play a big part in your work.
As I previously mentioned, you can ask for help on this Forum should you have any technical questions.