How to open a CSV file update some rows, columns, delete some rows and save it as another CSV file in VB.net?

You can use LINQ to load, remove and update your CSV, for example:

Const separator = ","c
Dim csvPath = "C:\Temp\USPresident.csv"
Dim datPath = "C:\Temp\USPresident.dat"
Dim rows = (From line In IO.File.ReadAllLines(csvPath)
               Select line.Split(separator)).ToList
' get all lines with specific value ' 
Dim presidentRows = (From cols In rows
               Where cols.Contains("William Howard Taft")).ToList
' remove these lines with Except'
Dim rowsWithoutPresident = rows.Except(presidentRows).ToList
' update some values '
For Each row In rowsWithoutPresident
    row(3) = "test-value"
Next
Dim newLines = (From cols In rowsWithoutPresident
               Select String.Join(separator, cols)).ToArray
IO.File.WriteAllLines(datPath, newLines)

Tested with this csv-file with US-presidents.

Option Strict On | Option Infer On | Option Explicit On