twrp install

Hey guys, I want to install a custom ROM (xiaomi.eu ROM) but I'm not sure about the steps that I have to follow. I read a lot of threads here but there's nothing clear in my mind so these are the steps that I think I have to follow. Please let me know if I am right: This is what I have right...

I downloaded TWRP from rom thread and placed it on Phone storage. but when I try to install it via "Choose Update Package" from Update menu. I get the following error Cant't veriy Update "Couldn't verify update package" I also tried the other method fastboot flash recovery xxx.img and fastboot...

I bought a redmi note 2 16Gb, I've been trying to install the twrp recover and I couldn't... I try to flash the twrp_hermes.zip by the updater app and it fails, I try to install using flashify app and nothing happens, I try to install by fastboot mode on PC (fastboot flash recovery recovery.img)...

Hy, guy's and lady's I'm having a big, and dumb, issue on my hands. The story begins with buying a Xiaomi RM3, when it arrived it had a custom rom on it (it had playstore and a ton of Chinese apps) After waiting 12 days for my unlock permission and trying for 2 hours to install developer...