With seus you cannt debrand your phone.
For flashing you need main firmware, filesystem (FS), and custum pack to custumise your phone.
Be aware, if you wont to have certain languge, then your FS and custum most be a match.
Beside the flash files you need praogram to flash, XS or setoollite, and important thing is the CID of your phone wich you can read with xs.