As stated above, the data can either come from within the same worksheet or from another file entirely. The difference is that you’ll need to use the IMPORTRANGE function for the data from an external sheet, as opposed to just using the equal sign ‘=’ for data within the worksheet. Be aware though that if you’re using an external file, if that file gets deleted, all cells with the IMPORTRANGE function will display either a #REF or #VALUE error signifying that Google Sheets can’t find the data being linked.