Where is the settings to check Use default Value in magento 2?
If you want all products have checked Use Default value
then run below sql in database:
DELETE FROM `catalog_product_entity_text` where store_id = 1;
DELETE FROM `catalog_product_entity_datetime` where store_id = 1;
DELETE FROM `catalog_product_entity_decimal` where store_id = 1;
DELETE FROM `catalog_product_entity_int` where store_id = 1;
DELETE FROM `catalog_product_entity_varchar` where store_id = 1;
In example code store ID 1
is ID of store. You need to check ID's of all store-views in admin and run the above code for each store-views.
PS: Make sure you take backup of database before sql query.