This is not custom rom. Its official rom by miui, but this rom has ben removed by miui.
I give you'r link because i save it 😂 http://bigota.d.miui.com/V8.5.10.0.NCCMIED/miui_HM4AGlobal_V8.5.10.0.NCCMIED_2c183b1523_7.1.zip
Go to updater, choose packages, update, reboot,
Or flash with twrp but you must flash "lazyflasher after flashing rom. Dont worry, your data not will lose...