How to find the approval email received to CPQ after approve

How to find the approval email received to CPQ after approving and where to find the received email are stored in CPQ.
Please give us the detailed steps to see the email received through approval.
How the approval email trigger from the CPQ for mobile approval

How to include the delegate approver of the approver in the email for send and reply
eg: To → mainapprover@company.com; delegatorapprover@company.com
In current system it can send both approvers but seperate email like
email 1 To → contains mainapprover@company .com
email 2 To → contains only delegatorapprover@company .com

How to make the chaining delegate approval eg: A has delegate approver as B and B has delegate approver as C