Dropdown - send and view table

I created a message system.
I have a dropdown menu that lists users registered through a database.

I use: {var:read_data} to show users

My problem is with viewin these messages because I need each user to see your message. According to login

I also need you to have the option to send to everyone.

Hi Rafael,
​
You can do this by filtering messages based on user id:

message.user_id:{user:id}

Best regards

thanks