Hi @lakshmipravallika ,
You can try the below 2 approaches.
1. Create a technical workflow. Fetch all delivery templates and add the default seed address to all delivery templates using JS. So that existing delivery templates and new delivery templates which will be duplicated of existing templates will have this default address added. But campaign operator can be able to delete the seed address from the delivery template.
2. You can create a control type typology rule and create a script to add the default seed address to all deliveries which uses this typology rule. And now assign this typology rule to all your typologies in the instance.