This page explains how to start and complete the Face the Frost Talus side quest.
How to Start the Quest
First, you need to complete the Divine Beast Vah Medoh Dungeon. Then you can talk to Gesane, who guards the bridge to Rito Village, to start the quest.
How to Complete the Quest
It will help if you buy the Snowquill Set from the Rito Village armor shop and have a Great Fairy upgrade it twice so you get the Unfreezable effect. Or if you have the Expansion Pass you can find Zant's Helmet and wear that to become unfreezable.
If you make this quest active in the adventure log, the location of the Frost Talus will be displayed on the map. Go there and defeat the Frost Talus, then go back and talk to Gesane to complete the quest.
Quest Reward
Gesane gives you a Silver Rupee.