Data entered in Notepad file should be comma separated.
For example if text file contains below data like two columns and in each row data content is separated by comma.
Now save the file as “test.csv” and Open It.
Else Copy below data as it is in text file. Use File -> Save As option and provide any file name with extension csv in inverted quotes like “test.csv” and save it.
double click on file and file should open in csv format.
Use below data to copy in notepad and save it as stated above. Or you can try to create your own data by adding comma in each row.
Also there are many online tools which are available on google to convert data from notepad to csv but again security of data is always matters.
So try use tools which don’t store any data or don’t perform any server call.