To display the sub-collection list within a collection, follow these steps. It works with the metafield option, so create it by following the steps below.
Step 1 :
Go to Store Admin > Settings > Metafields and metaobjects > Collections > Add definition
Follow the steps marked in the image below.
Step 2 : Now go to the collection page in store admin and scroll down to the metafield section.
Click on the “Sub Collections” field and select collections.
Step 3 : Now go to the sub collection section in theme customize and click on the “Dynamic Source” button and select “Sub Collections,” then save the page.
