Rock 5B Booting from EMMC When No SD

I’ve got a rock 5b board that the SD card is broken , i had been booting to a SSD which died. if i grab a EMMC Module online and flash it with the correct OS will the Rock 5B Boot from it instead ? Also if i just want to use it to boot and then install to a replacement SSD will a 16GB EMMC module be big enough ?

Should be enough

Do you mean to use EMMC to start the system and burn the system image to SSD? That is enough