do you know servier medical art (http://www.servier.com/Powerpoint-image-bank) You can use the figure elements for teaching purpose, as well for non commerical publication (if seen them occasionally within papers).
The best, in my opinion, is Adobe Illustrator and that's very expensive. There are a few free softwares that can help you, but they may not exactly match the capabilities of AI. And not all of them are compatible with Windows (some of these are for Mac, and some for Linux platforms). Unfortunately, I don't have much experience with any of these. So I cannot tell you which one will best serve your need.
you can buy Motifolio power point tool kit a bit expensive. for free I found servier medical art (http://www.servier.com/Powerpoint-image-bank) is very easy a
BioRender might be a good option (https://biorender.io/)
It's an online app that contains a library of pre-made cells, proteins, membrane shapes, organs, lab equipment, etc. that you can drag-and-drop so you don't have to spend time drawing each element of the figure yourself. Saves a LOT of time and the final figures you create are professional-looking. Plus, it's free for educational use.