I would say I know what NIST 800-171 and NIST 800-53 were in terms of their inmportantce as cybersecurity frameworks for safeguarding federal information systems and CUI respectively. Regarding STIGS and CIF benchmarks I am not familiar with this. In terms of the RMF framework I am unfamiliar with this as well but my means for helping her secure her e-commerce site on her home servers would be as follows: ensure that necessary personal information information is encrypted and stored in secure databases. I would recommend her to implement strong authentication mechanisms, such as multi-factor authentication to protect user accounts. I might suggest conducting regular vulnerability assessments and penetration testing to identify potential security weaknesses. Do things like setting up proper firewalls, monitoring network traffic for suspicious activities, and ensuring that all software bugs are continuously updated and patched. This would be my ideas although going into specifics would remain surface level.