Hi @Aryan,
To answer you question directly - Assignment rules are not isolated to Incident, they can run against a whole host record related tables - eg: Incident, Problem, Change, KB and so so many more.
Take a look at the Assignment rules already provided for you. Type 'Assignment Rule' in the Navigation menu under 'Routing and Assignment'
To help others (or for me to help you more directly), please mark this response correct by clicking on Accept as Solution and/or Kudos.
Thanks, Robbie
