You'll want to get your composition right for this. Basically a big fight scene is like a big crowd scene. Lots of people doing stuff in one picture. The thing that contextualizes these types of scenes is picking one "focal point" of the scene, and making sure the business in that area of the picture is super clear. Clear posing, clear rendering/details/contrast, etc. Then, from the strength of that image, the viewer can "resolve" the rest of the scene, and you gain the ability to render the other stuff less. And in the very distant BG, you can just put little flecks of brushstrokes and it'll read. Take a look at some of Craig Mullins' battle scenes for great examples of this.

Hi Angel! You know, I think the mistake many creators make is to think the first step is getting out the pencil and drawing. I would very much encourage you to get out a whiteboard - as large of one as you can - and just start jotting down notes that broadly capture the scope of what you want to create. As for getting story down, that is obviously a separate discipline entirely (and I recommend the Story Grid podcast for great insights into the structure of storytelling,) but you'll want to map out your 3-Act structure, and then break each act down into its own beginning->middle->end. A whiteboard is great for this because the marks we make there feel "disposable." When you draw in your sketchbook or something, it feels like it needs to be good. But we can't have that at the beginning. Storytelling requires massive amounts of revision - both big and small - and you need a medium suited to sorting all that out. I just YouTubed Marshall Vandruff's whiteboard lecture, which I watched some time ago. This is about career planning, but really he's telling you how you can use a whiteboard for any kind of planning: https://www.youtube.com/watch?v=AblcTu7WFlA Also, on a whiteboard you can draw thumbnails and stuff too, to go along with your written ideas! Once you have something there that you feel you can begin with, then suddenly you can try putting some of that material onto paper and panels. And Proko has some great vids on that, including the one that was just released this week, by Ryan Benjamin! https://www.youtube.com/watch?v=70Z8iY0Q2Gw Last bit of advice: give yourself LOTS of time, and try to noodle away at it for at least 10 minutes every single day. The momentum is what you need on your side. Good luck!