Starting with a CSV file, like the following one, open it in Excel by using the standard Excel file opening, using keyboard shortcut CTRL+O, or by opening it in Windows Explorer with right clic and selection Open with Excel 2010 / Excel 2013 / Excel 2016, depending on the version you have installed.
Each row has been put in one single cell, while you might want them to be separated by columns, therefore the upcoming steps.
As the comma delimited file format is text only, if it is storing any column with numbers, MS Excel might recognize at this step these columns as numerical for example.
In some cases, it might be correct - if the column really only contains numeric values.
But in other cases, it might be wrong. Excel bases its detection of the column format on the first 100 rows, but it might be that a column has numbers only in the first 100 rows, but contains text afterwards.
If the format Text has not been chosen, then they will be detected as numbers, and an error will be displayed.
Another case, if a number like a barcode is stored, for example numbers 001234, then, Excel will detect them as numbers and store only 1234, while they should be stored as text 001234.
Simply click on the first column, then while holding Shift butting, click on the last one of your selection - you can also add columns to the selection by holding Ctrl and clicking on the column - then select Column data format as Text to format them all as text and lose no data.
Column format can always be fine tuned as necessary afterwards.
A CSV (or Comma Separated Values), is a plain text file which contains the equivalent of a spreadsheet, or a table, stored as plain text. Each cell is typically separated by a comma, therefore the name, but another character can be used, for example tabulation or semicolon.
How to force excel to open csv files with data arranged in columns
This is not possible directly. Data has to be opened as explained above, and then arranged to columns.