Formatting Not Retained With CSV Files

1. Open notepad file. Type 01. Save it as "Book2.CSV". Close notepad.
2. Open Book2.CSV in excel

You will see that 01 is shown as 1.

I would like to retain 01 in Cell A1. How do I do this in CSV?

I know how to retain formatting in excel but not in CSV. You can do the following in Excel files:

In the cell A1, right click and choose 'Format Cells'. In the Number tab, choose the category as Custom. In the Type on the right hand side, I type in 00. The value 1 in the cell A1 gets converted to 01.

My question:
1. why is this formatting not retained with CSV files?
2. Is there a way to programmatically (macros) to correct this?