Provision a Redis cache specifically for a single schema on an AWS PostgreSQL RDS

Is it possible to provision a Redis cache specifically for a single schema on an AWS PostgreSQL RDS, and what strategies can be employed to ensure data consistency between the Redis cache and the PostgreSQL database?

I have a db.t4g.2xlarge database with multiple schema. I want to spin up a Redis or Memcache for One schema, because its it most queried schema.