@William2673
Welcome William & Christy!
You can Add Christy as a Co-Host as mentioned. She would need to create her own Airbnb profile and then you send a email invite link to invite her to Co Host. Be sure to send it to the email address on her Airbnb profile. I suggest using a computer to send it and accept it. Sometimes the links don't work in the App.
Just to note...
Even a full-access Co Host will not be able to access your Scheduled Messages/Quick Replies and the Host Guidebook. It's very strange, but that's the way Airbnb does it. Christy can copy and paste your messages under her Co Host access if she likes. However, she will not be able to see or edit your Scheduled Messages/Quick Replies Templates. She will see guest messages though and have full access to the listing and calendar.