Default Custom ROM erased

Hi everybody, I need some help! I by accident erased the custom ROM in my one and I now can only access the recovery mode. I don't have the custom ROM file in the memory to flash it and cannot access the internal memory by any means that I know so that I transfer the ROM file to flash it. What can I do about it? Do I use Odin? But what ROM will be safe to install? Any advice or solution would be appreciated.

Thanks

Ed

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