Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. It shares its reading with the word 備える, which you learned a level ago, but in case you need a reminder, here it is:
What's the best way for your servants to make an offering? When they offer up their sauna (そな)! You really value a warm and relaxing sauna session at the end of the day.
Can you buy some flowers to place on the graves tomorrow on your way home?