Whatever generates the CSV file needs to wrap the fields in quotes
"field 1", "field 2", "this, that"
then your code needs to treat only commas outside of quote pairs as being the separators so that it knows "this, that" is a single field and not two. There are various libraries out there that will already do this for you if you google "c# csv parser"
C# - Light and Fast CSV Parser[
^]