Writing Technical Book for Computer Literate People – How much are they expected to know

Hope this is the right forum

I'm self-publishing a technical book (using MS Excel for creating Data Visualizations) that includes step-by-step instructions with screenshot.

Book is targeted towards computer literate people who don't have technical/engineering background and wish to get into that field. In other words, your average person earning about $30K a year who wants to break into IT field.

I find myself explaining how to copy/paste/change font color. Is this necessary or should computer literate people be expected to know this.

What else should computer literate people be expected to know? Explaining how to copy and paste something seems to be taking up extra space.

Thanks

EDIT: Computer Literate means can read/write/send email, text. Can upload videos to YouTUBE. And can fully participate in social media, i.e. Facebook, Twitter, Instagram, etc, etc