ROM Hack Need an introduction to 3ds rom hacking

[storm75x]

Hey there, the hacking scene caught my interest recently and I wanted to join the.. cult.
So here we go, I have been playing various games such as Pokemon and Rune Factory 4, and those games were great games that would be even better modded.

Pokemon aside, since they got noob friendly programs which kinda killed the thrill, I want to learn how to tackle this hell of a puzzle by using RF4 as a base.

I would like to learn various things such as
- ROM decrypting and encrypting
- Extracting and packing
- Editing the codes (I just need to know how to access it)
- Replacing texture/models
- Anything useful

Thanks in advance!