Here are the options available for your users.

Non logged-in user reactions: Allow everyone to react to your posts or not.

Redirect non logged-in users: Send your user to a URL of your choice. Leave empty, if you want to activate the on page message.

On page message for non logged in users: Leave an error message instead of redirecting you user. Please note that a redirect overrides the message field when both are populated.

Multiple Reactions: Controls whether a user can react once or multiple times.