One way is to use for example use
File.ReadAllLines[
^]. This would get you an array of string. For each string in array use Split method to break it into columns. After that use those string arrays as parameters for your insert statement. So something like:
string[] fileLines = System.IO.File.ReadAllLines("somefilename.txt");
foreach (string line in fileLines) {
string[] cols = line.Split('|');
}