Yes, customers can use their Store Credit to purchase any product in your store with Magento 2 Store Credit Extension. However, you have the flexibility to exclude specific products or categories from being eligible for purchase using Store Credit if desired.

Read this How to Configure Store Credit Extension in Magento 2 Store to setup this extension.

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

• Maximizing revenue with Magento 2 Store Credit Extension
• Raise Loyalty & Returning Visitors with Magento 2 Store Credit Extension
• Store Credit in eCommerce: A Key to Customer Retention