Hi Hartmer,
Follow this guide to flash TWRP: https:/ /twrp.me/devices/ xiaomimi5s.html
For fastboot I used this link https:/ /forum.xda-developers.com/ showthread.php?t=2317790
Having TWRP is very handy in case something goes wrong or if you switch rom (linageOS, RR..etc)
Simply install the ROM via TWRP once you've flashed it. You can still copy files from a pc via USB when in recovery. You can find the latest rom in the 'ROM DOWNLOADS' section of this site.
I'm using the latest xiaomi.eu on my Mi 5s and it is a fair improvement compared to global beta.
Take a good read of everything before making any modifications.
