Read Text File in Visual Basic 6

 Function ReadTextFileContents(filename As String) As String

    Dim fnum As Integer
    fnum = FreeFile()
    Open filename For Input As #fnum
    ReadTextFileContents = Input(LOF(fnum), fnum)
    Close #fnum
   
End Function

reference:
https://www.chilkatsoft.com/
https://support.microsoft.com