Are you trying to get all of the values from all users or just one user? It’s going to be difficult without knowing the user id and without knowing the field names to look at. You can get the field groups if you have a user id and loop through the fields in that group, but without a user id there is nothing built into ACF to get the fields. You could construct an SQL query and get the values from the usermeta table (https://codex.wordpress.org/Class_Reference/wpdb) but you’ll need to have the field names.
