installing xiaomi.eu rom

[unzeunze]

so i'm a bit confused with installing the xiaomi.eu rom on my mi mix 2s

do i always have to first unlock the phone? with the 72 hour waiting period

after its unlocked i just need to follow the steps here https://twrp.me/xiaomi/xiaomimimix2s.html ?
like download the app or do it with fastboot? or do i need some extra steps between this.

i found many solutions with different ways, so i kinda dont know if this is all it takes or if i have to do more.

appreciate all the help and thanks in advance!

and sorry if these kinda questions are asked a lot

edit: have the latest global version installed.
if i do it with the app, do i need to download the twrp data before that? or is it integrated in the app, so i just have to select it and the app downloads it

 

[unzeunze]

thank you for your answer! appreciate it, but one last question.
if i follow all these steps until magisk and do that (or until the trwp), do i still have to install the xiaomi.eu rom after that? or was that included there?
thank you for your time!