As a perfect beginner is a big challenge to take on this one without having a minimum set of skills and must haves. I'm enumerating them in no particular order
Digital electronics knowledge - you need to understand gates flop flops clocks etc. and how they interact.
Mathematics - Boolean Algebra - simple boolean functions AND, OR, NO, XOR and more complicated constructs The De Morgan Theorem is a must conditions (IF) and others. Ideally you should understand the link between Boolean Arithmetic and Digital electronics (they kinda work hand in hand)
Analytical thinking - you need to be able to think in an analytical way, to understand structures and hierarchy. Thinking simple and practical is a must. Prior knowledge of programming can help but in the same time can become a drag.
Time (not a skill) - You need to be patience this domain requires a lot of learning over long period of time. At times the FPGA jargon and the large number of new terms can be overwhelming.
I created a video where I'm talking about this is you prefer to watch instead of this boring text.