In Learning Mode ASM adapts the security policy so we can prevent false positives. This is called Policy Building. Learning Suggestions are created which you can Accept, Delete or Ignore.
If we talk about Enforcement Readiness Period we talk about staging. For example Signature Staging. If you have Signatures configured in your ASM policy and your ERP is 7 days, Signatures which did not trigger a violation within those 7 days are set to Ready to Enforce. You can choose to enable those signatures.
I would advise you to follow the instructor led ASM training.