STI information

So a few weeks ago my mom went to the pharmacy to pick up a prescription. She didn't tell me what it was for but she left it in my car and so I dug it out and realized it was for either chickenpox or herpes. She doesn't have chickenpox so I assume she is suspecting she may have got herpes??? I just need to know more about how it's spread just in case she does have it. I would like to stay healthy😉