A text-based, free tutorial for Lotus 1-2-3 Millennium Edition vocabulary, commands and functions is available at EmpowermentZone.com. Amazon.com offers books on Lotus and IBM's SmartSuite. Lotus 1-2-3 tutorials are hard to find, and books are expensive relative to other software tutorials because IBM has not sold the product since 2013 and support ended in 2014.
Unless a workplace or class specifically requires Lotus 1-2-3, there are more tutorials available for current software, such as Microsoft Excel or LibreOffice Calc. LibreOffice is free, open-source software, so there is no expense to acquire a legal copy.
Microsoft publishes Excel tutorials online. Available tutorials use approaches by product or by scenario. The product tutorials are specific to both the Excel software and the operating system, such as Excel for Windows, Excel for Mac or Excel for Android. Android and iOS versions of Excel are free downloads. The scenario tutorials move through a task, and thus may require other office products to complete the work.
TheFrugalComputerGuy.com offers LibreOffice Calc tutorials, among other LibreOffice tutorials. As with the Excel tutorials, task-based lessons often use additional free LibreOffice programs. These tutorials cover basic use through advanced scenarios.
Lotus 1-2-3, Microsoft Excel and LibreOffice Calc all have significant online help systems that are accessible through the software's menu. Online help is useful to new users who need to know concepts and vocabulary and wish to learn by exploring the software.