How can I alter the default sort in my Avatar 1.2.2 theme store?

Store Design
1

How can I change the default sort by my store link is https://fashion4less.co.za/collections/all My store Theme is Avatar version 1.2.2.

Products-Fashion4less-co-za.png
Products-Fashion4less-co-za.png1437×703 88.7 KB

2

My store Theme is Avatar version 1.2.2.