sorry, you could be so kind as to make me understand in detail how to root the phone? and from how I felt if there is the possibility to remove the initial security message
You have to flash TWRP to be able to install Magisk, but then you just install Magisk in TWRP and boot to system. Then install EdXposed in Magisk as a module.
I remember you can remove the text from the boot saying changed state but the delay remains so I not bother.