The configuration settings can be opened from the Marketplace > Vendor Configuration in the menu section.

1. Enable Singapore Post Shipping For Vendor
   When set to Yes, Vendor Singapore Post shipping will be enabled and the vendor will see this option in the vendor shipping method panel, otherwise, Singapore Post shipping will not be available for vendor.
   
2. Enable Singapore Post Shipping Method From Admin
   This module is based on the Singapore Post shipping method for Magento 2 so this module should be installed beforehand. So the Singapore Post shipping method should be enabled by the admin.

   Admin can enable the Singapore Post shipping method by going to the Stores > Configuration > Shipping Method section. Here you will see the “Singapore Post Shipping” group and set the “Enabled” field to “yes”. Now the Vendor Singapore Post shipping will be available to the vendor and the customer will see Singapore Post Shipping rates on frontend at the time of checkout.