Hi!
Great that you want to help us moderate!
Do you have a lemmy.world account? That’s needed if we want to transfer the community to you.
If you have, please link a post where you have commented, so I can transfer the community to you.
What do you mean? Marking your notifications in your inbox as read or posts?
Via the website, there is no way to delete the view history. Maybe some third-party apps offer this function. I suggest to contact the developer of the specific app for that.