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.
In all spreadsheet programs including Microsoft Excel, rows are labeled using numbers (e.g., 1 to 1,048,576). All columns are labeled with letters starting with the letter A and then incrementing by a letter after the final letter Z. For example, after the letter Z, the next column is AA, AB, AC, ..., AZ and then incrementing to BA, BB, BC, etc. all of the way to the last column XFD. When working with a cell, you combine the column with the row. For example, the very first cell is in column A and on row 1, so the cell is labeled as A1.