To get a functional setup, you need to download a combination of the custom recovery, the ROM system image, and Google Apps (if not pre-included). 1. Custom Recovery (TWRP)
You will need a custom recovery like TWRP (Team Win Recovery Project) or OrangeFox modified for the Oppo A5S to wipe partitions and flash files.
Your OPPO A5s isn’t dead. It’s just waiting for a new soul.
This process will wipe your entire phone. Back up everything.