When I get a message in signal that that it has specific wording that would make someone think that it’s a task then I get a notification to save it to keep how is Google doing this are they reading my signal my messages
Assuming this is on an android phone with the normal Google Play Services on it then you should expect that Google can theoretically read anything that appears on it. It’s probably not that sinister though, I don’t imagine anything is being sent away and logged (though it theoretically could be!), there’s probably just some process which reads every incoming notification and if it thinks it sounds like a task then it offers you the prompt. Is this some setting you haven’t disabled in Google Assistant?
I believe signal uses google to push the notifications and if its giving you the option to add it to google keep the phone obviously know what it is the message content.
I think that is a feature of Google Assistant or some other Google product. It reads everything you have on your screen at any moment to give you “smart” help like easy opening of addresses or phone numbers.
also your keyboard might be leaking data too
That’s why I disabled network access for my keyboard.
That doesn’t prevent it. Keyboard is tied to many core OS processes that connect to Google servers and relay that information. I would recommend replacing it with OpenBoard which is based on Android Open Source Project.