There are lots of spreadsheet packages. What you will want to get depends on what features you need, how much you are willing to spend and what operating system you are using. Google Sheets is free and has most of the basic spreadsheet features, and is accessible online (and you can use your Google Sheets offline too). Microsoft Excel comes as part of the Microsoft Office suite and is one of the most commonly used spreadsheet packages. OpenOffice is free, can run on Linux-based systems, and consumes less memory than Microsoft Office. Lotus 1–2–3 was one of the first and most widely used spreadsheet packages back in the 80’s-90’s but it has been overtaken by Microsoft Excel in terms of popularity.
Below are examples of spreadsheet that can be downloaded and this spreadsheet helps illustrate some of the capabilities of a spreadsheet, formulas, and functions used in a spreadsheet and allows you to experiment more with a spreadsheet.