All information is available online, but I like books, because they are structured. I read this book and I think it covers all basics you must know. It's short and doesn't go too deep into details. I think it (or something similar) can be a good start for you.
Investing QuickStart Guide: The Simplified Beginner's Guide to Successfully Navigating the Stock Market, Growing Your Wealth & Creating a Secure Financial Future
https://www.amazon.com/dp/B07H71XXGY/ref=cm_sw_r_cp_apa_i_yFcHDb6JE0CMD
Literally one of the chapters.