I have recently noticed a symbol like this 《》 in the notification bar but I don't know what it means and it only disappears when I bring up the keyboard
Welcome to the forums! Which phone do you have? Can't you get more information swiping down from the status bar? TalkBack has a similar icon but your phone should behave differently if it was activated. Could you post a screenshot to have a better idea? Just in case check in settings - accessibility.