1)Get a cardtrige game with any update between to 4.1-4.5.
2)Install emunand and back up your nand.
3)Install a CFW like rxTools that allows you to play cia installed games, get a cia manager too.
Optional:
4)Update to 9.2 using sysupdater and autoboot your CFW using Themehax.
I suggest you to take a good time reading before going wild.
Here is a complete tutorial to install rxTools from scratch:
https://gbatemp.net/threads/tutorial-installing-rxtools-custom-firmware-3ds-and-2ds.390867/
Before you do anything make sure the update you se in the cardtridge is from 4.1-4.5 not a single digit more, to use the MSET exploit.
You will be unavailable to hack it otherwise, becuase 3.0.0 <- - That number 0 means you don't have an active web-browser, if you go over 4.5 you won't have access to a Kernel exploit.