If you're just starting with Chivalry modding, check out Tutorial: Creating the "Giant Slayers" mod
If you're just starting with learning to code in UnrealScript for Unreal Engine 3, your main resources will be:
Important UDN pages:
Supplementary documentation here on our Wiki:
- Modding Guides – step-by-step guides
- Replication – a supplement to the UDN "Networking & Replication" page, including some common traps you might fall into, and hopefully clarifying some things that might not make sense on the first read of the UDN documentation.
- UE3 programming pitfalls – some common problems and mistakes that might arise as you work with UnrealScript
- Kismet – explains some things about Kismet from a programmer's point-of-view
If you'd like to see an example of a Chivalry mod, check out:
In terms of programming in general, you'll want to be at least familiar with Object-Oriented Programming, which is the paradigm that UnrealScript follows. That's beyond the scope of this document, but there are many resources, courses, books, etc. out there on the topic.