security – encryption of SharePoint and OpenPGP files

If I have SharePoint in a blue cloud that can be accessed from any computer using a browser, is it possible to integrate the PGP encryption on the client side so that when the files are loaded, they are on the client side encrypted and then stored in SharePoint , and when the files are downloaded? Or are they opened, decrypted on the client side and encrypted again before loading / saving?

Ideally, I would like to configure it so that the encryption and description are performed automatically if the client side has OpenPGP keys, but that could be driving it.