latest bios is 3401, you can flash it if you like but you may not need it. If you had a 7700k I would have suggested getting it only so it recognised your CPU but you shouldn't need it. Really depends on which BIOS version you have now
3401 current
3016 - add support for 7 series CPU
2103
2003
0311 - release version
your manual -
http://dlcdnet.asus.com/pub/ASUS/mb/LGA1151/Z170_PRO_GAMING_AURA/E11776_Z170_PRO_GAMING_AURA_UM_WEB_only.pdf
judging from fact the section about installing an operating system only covers win 7, I don't think there is anything in here you need to change first.
You may want to set up ram in XMP profile but this isn't something you need to do before installing win 10. I also wouldn't overclock CPU before installing windows as that can lead to errors.