It's free...which is great! This means your Zotero library can follow you throughout your college career and beyond.
It's free....which can be not so great. Zotero can make mistakes and metadata for items can be incorrect. Remember to always check and double-check your citations with an authoritative and up-to-date citation guidebook.
If you can't find an option, right-click! Zotero often makes use of contextual menus that provide many options that can't be found unless you right-click.
If something isn't working right, Zotero forums are a great place to get your questions answered. This is an open source project and tons of people devote their time to fixing Zotero bugs!
Feel free to contact the librarian listed on the right of the screen if you have any questions about using Zotero.