For 99% of users: The risk of a permanent brick is extremely high. Unless you are an advanced user with MTK flashing tools and accept the risk, stick to debloating the stock EMUI.
You will need a custom recovery like TWRP (Team Win Recovery Project) ported for the Y5P to flash files.
: A free tool that requires opening your phone to short a "testpoint" on the motherboard to bypass security.
to bypass security, though this often requires hardware manipulation (shorting CLK test points) and carries a high risk of bricking the device. ROM Availability and Alternatives Y5 Prime 2018 unlock bootloader procedure - HUAWEI Global