You’re talking about through FaceTime, right? Or is there another native screen sharing app that I am unaware of?
After you open it, press “Connections -> New” and start typing a contact name.
They get a little notification if they are online, and if they accept you have a seamless screen sharing experience ready to go. It’s honestly magic for the “my parents have an error message and don’t know what to do” situation.
I assume they have you in their contacts as well for it to work.
Glad to see your parents are tech savvy, but this reads like you live in a very different reality from mine.
Your parents don’t need to run the app at all. You need to run the app.
Unless you really do live in a different reality where you want your parents to help you out when you see an error message you don’t understand?