If you want to set only certain products that can get loyalty points if they are sold in the post you can use enable or disable loyalty point to each product or variant. You can do it by following this steps below.
Step 1. Select variant you want to disable earning point when sold
Step 2. Select Edit in variant details
Step 3. Select "Yes" to enable loyalty point or "No" to disable, then Submit
Step 4. Customer buy product that you set loyalty point enable as "No"
Step 5. Customer Point not Increased
