You must install a tool like TWRP (Team Win Recovery Project) or OrangeFox Recovery to "flash" the ROM files.
If your ROM doesn't include Google apps, flash a GApps package immediately after the ROM. Reboot: The first boot can take up to 10 minutes. Final Thoughts Galaxy A50s Custom Rom
While each ROM has specific instructions, the general workflow for the Galaxy A50s is as follows: You must install a tool like TWRP (Team
Use the Odin tool on a Windows PC to flash the recovery.tar file to the AP slot. Galaxy A50s Custom Rom