With iOS15, you can share whatever is currently on your screen with someone via Message. Doing this via Siri can be more accessible compared to manually taking screenshots and sending it through Messages.
How to share your screen with Siri
Say "Hey Siri" to prompt Siri
Follow this up with "Share this with [person]"
Before sending, Siri will confirm by asking you "Are you ready to send it?"
Reply with "Yes", or add more context to the photo with a comment and tap Send
If the source from your screen is a webpage, Siri will send it like a URL to that specific page. However, if it's something like the weather, Siri will let you know that it can only take a screenshot. If this occurs, reply with "Ok" so Siri will continue.