[Q] ROM SOS SOS galaxy s4 att topic

hello

i have att galaxy s4 MK2 i root it and have su and su checker everything working...
now i am trying to instal room i downloaded the twrp and its not working or maby i dont know what i am doing...
pleas i need halp some tipe of guide that will show step by step how to rom my galaxy s4.

any rom is good i cant handle att rom....

pleas any guide how to rom...
thank u