Can you use SharePoint without having Office 365? Thanks!
Office 365 is complete suit of products which include Office, Exchange, Lync, Yammer, AD, Sharepoint. Check this
If you want to use only SharePoint, then you need to buy the SharePoint online plan...Select one plan which fit your needs
Now another Option is, You can install the SharePoint on prem. That's mean you need to install the SharePoint either free version(SharePoint Foundation) or you have to buy the SharePoint Server license, you need the Server Hardware, as well as SQL Server & Windows Server OS license as well.