[icebraining]

I'm going to guess you're a technical user :) my parents would never think to search for standardized or GDPR-specific email addresses. What they did was find some generic way to contact the company (phone number, possibly Facebook or email) and ask them "where should I send a request for you to delete my data?"

Regarding the content, they would find some template they can mostly understand, then change/add a paragraph to include whatever specifics they need.

As for verification of identify, they would not even think much about it. They would sign with their name, and of course send from their email. The company would have to reply back to ask for whatever they need to verify it properly.