meizu m3s custom rom.
Meizu m3s

First, you need to unlock the bootloader. (Not possible yet)
Install custom recovery (No unlock bootloader will not run)
Without unlocking the bootloader custom ROMs will not install.
Meizu locks all methods of unlocking, only modding the bootloader will work.

hello, how to find the bootload modded ans install it on m3s please

Meizu m3s

There is only one successful mod, it is unfortunately only for the m2 note. The m2 note: https://forum.xda-developers.com/meizu-mx/orig-development/tutorial-meizu-m2-note-bootloader-t3429843
The risk of modding is high as it may likely brick your phone.

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