I have a N3ds with arm9loaderhax, and emunand. I try launching a dsiware and i get an error telling me to restart the 3ds. Do i have to install the games on sysnand or use the n3ds twl patch cia on the luma site?
Yes.
You don't need to install the TWL_FIRM patch though, Luma3DS has it built in (and in fact installing it might cause problems)
If you play GBA/DSiWare on a regular basis you would be better off flashing your emuNAND to sysNAND and just using that so you don't have to deal with this. However, if you play them infrequently you can install them to sysNAND only if you want and just boot into sysNAND CFW when you want to play them.