In which sections of AWR and Statspack can we identify how much CPU the database usually consumes?

We need to migrate a database, but we need to evaluate the possibility of reducing the number of resources (CPU) to decrease the number of licenses. In which sections of AWR and Statspack can we identify how much CPU the database usually consumes? I mean, if we have 16 cores in the server and usually it consumes only 12 cores, how can we check it?