To enable in-store delivery in Magento 2, go to Stores > Settings > Configuration > Sales > Delivery Methods. Select the In-Store Delivery Method and click Enable.

You can use our Magento 2 Store Pickup Extension to offer buy online and pickup in store method to your customers.

Read this How to Add In-store Pickup Functionality to Magento 2 to setup this extension.

Here are the few more resource to help you get most out of this Magento 2 Store Pickup Extension.

• A Comprehensive Look at the Store Pickup Trend in Ecommerce
• Store Pickup Extension for Smart Omni-Channel Magento Stores