I want to read audit log through SYSLOG of Scylla DB enterprise on UBUNTU 22.04, I want to send to external server how could I achieve that, any changes is needed in Configuration or not?

Only this Particular link I found for syslog nothing else.

ScyllaDB Auditing Guide | ScyllaDB Docs

This is the only needed configuration on Scylla side.
You can define a third party tool like syslog-ng to stream these logs somewhere else.