To block someone in the Meet section, expand their profile using the "^" arrow > scroll to the bottom of the profile > select block profile > choose the reason for blocking and they will be blocked from your view 

To block someone from the Feed, tap on their profile circle to view their profile > expand their profile using the "^" arrow > scroll to the bottom of the profile > select block profile > choose the reason for blocking and they will be blocked from your view 

To block someone from a message, select the ‘…’ icon in the top right-hand corner of the chat view. Select ‘Block (profile name)’. Once they are blocked, the other person will not be able to see your profile and you will no longer see theirs.