MIUI Express for Find 7a | XDA Forums
Download Xiaomi ADB: XiaomiADB.zip. Now find and download Redmi 7A Official MIUI ROM for Recovery. Start your device in Recovery mode and go to "Mi Assistant". Unpack downloaded archive with Xiaomi ADB to "C:\" drive. Move downloaded ROM to the same folder with ADB files.
Download Redmi 7A MIUI ROM Latest Update Flash File
Xiaomi Redmi 7 specs compared to Xiaomi Redmi 7A. Detailed up-do-date specifications shown side by side.
Xiaomi Flash Tool - Official Mi Flash Tool
I found a portable version (no installation needed) here: https://miui.blog/any-devices/mi-flash-tool/ Download (and extract) the MIUI Fastboot ROM for your device. This website has for almost all Xiaomi device.
Redmi 7A ROMs, Kernels, Recoveries, & Other Develo
If you are looking for the original Xiaomi Firmware (Stock ROM), then head over to the Xiaomi Firmware website. Download the official Xiaomi Flash Tool to flash or install Stock Firmware (ROM) on devices running on Qualcomm Chipsets.