Power Query separates data preparation from worksheet calculations. Data > Get Data opens a source in the Power Query Editor, where each transformation becomes an Applied Step. The source stays unchanged, and the steps describe how to build the cleaned result again.
After importing a file, inspect its headers and data types. A number stored as text can't be summed reliably until it has a numeric type. Trim unwanted spaces before filtering or matching names, because Pine and a padded version of Pine are different text values.
Use the preview to check the result after each step. Removing a column changes the output table, while filtering removes rows from the result. Neither action deletes records from the source file. When the result is ready, select Close & Load to write the current query result into the workbook. Closing without loading leaves that handoff unfinished.