Hi, I am from Brazil too. I have two methods for you.

Method 1 - Fastboot mode

You can try to flash the Offcial MIUI ROM (11.0.10 Global Stable) using fastboot. Maybe can work, even with locked bootloader, with MI Flash Tool. But this method can brick your device, so i do not recommend this way. And your phone needs to be the Global version too. Global Phone = Global Rom.

Method 2 - MI PC SUITE

I sugest that you also take a look at this link: https://c.mi.com/thread-2224746-1-0.html

MI PC SUTE can also work, and is the safest method to restore your phone, even with a locked bootloader. Using this method you will need MI PC Suite Software and the RECOVERY ROM for your device, but It needs to be the SAME ROM for  your device version. So, if your Redmi Note 7 is the global version, you need to download the Global Rom. If you phone is the Eropean version, you need to download the Eropean ROM. The device version and ROM version MUST be the same. Also, you DONT need to use fastboot or have a unlocked bootloader to use this method, which is good news. So i wish you good luck.