I include my boss because I have different backups for five or six different parts of my job, and my boss is more likely to know the nuances of which one is the appropriate contact than the person sending the email, so it’s more likely to get to the right person if she redirects than if the emailer tries to guess which one of the six contacts I listed is the one who can solve their problem. (My specialty is the “other things as requested” section of my job description; I’m sort of a jack of all trades around here. :) )
Education Details: Template #1 Out-Of-Office Old School Style: For those who want to keep it low key. Thank you for your email, I’m currently Out Of Office till . I’ll be replying to your mail once I return. However for time-sensitive matters, please reach out to my < teammate / Boss> at in my leave.

Website: https://www.ringcentral.com/us/en/blog/tuesday-tip-set-up-a-custom-holiday-announcement/
Given free rein, I’d absolutely love to tell people that needing me to show them how to do X in Excel is actually not a vacation-interrupting emergency and there are tons of free videos that would explain that, if they did not want to contact the actual departments who handle tech support and training. Or that this project they’ve known about for a month but decided to keep under their hat until it became an emergency is something they’ll need to resolve themselves. But that would not fly at all.