Planning to install Linux Mint, what should I know about it?

Hello everyone, after few weeks I will download Linux Mint because Window 10 will no longer be supported, I have an old laptop and I'm not planning to buy a new one. So Linux is the only solution here. Before installing it, I want to watch some vidoes about it and see what's the difference between it and Microsoft. I was wondering if anyone of you can share some mistakes you made while using Linux so that we can all learn from each other. I hope it will be easy for me, I use my laptop for work too and I am accountant so I had to use excel.