Disclaimer: Modifying your phone’s firmware carries risk. The author is not responsible for data loss or further damage. Always backup your data before flashing.
Because this model uses a processor (unlike the older Qualcomm version), it is actually very hard to permanently brick. In fact, the dreaded "dead boot" (no response, no LED, no vibration) is usually reversible. How to Unbrick XIAOMI Redmi Note 8 2021
A: That is the "disconnect/reconnect" loop. Your battery is too low. Let the phone charge via a wall charger for 2 hours, even if the screen is black. Disclaimer: Modifying your phone’s firmware carries risk