my charger serial number is *******/A this charger adapter is original

This is a user helping users with tech questions forum, we are not apple and apple do not read your posts here

to the best of us users knowledge How to identify a genuine adapter using s… - Apple Community

then there is no way you can be sure other than purchase it directly from an apple or apple certified store

the serial number is no guarantee

you can attempt to seek verification of that fact using their official support channels

 Get Support (apple.com)

And or

 Contact - Official Apple Support

And or

Contact - How to Contact Us - Apple

Or

Genius Bar Reservation and Apple

Support Options - Apple

There is not a website to check if the serial number of a charger is original. The only way to know for sure is to purchase from Apple or Authorized Apple seller. The counterfeit market is huge for Apple accessories, so I would be suspect of any purchase from a third party site.