I’m not understanding your problem fully.
If you would like to compare the datetime, I would recommend keeping it as a datetype so the format is consistent and let’s you compare dates together.
So you can do for example, datetime = Now or datetime < Now
If you do want to convert to string then you can do datetime.ToString or .ToShortdatestring like Arivu mentioned
If you would like to filter a date table by the datetime, then I would suggest looking at the .Where method which let’s you use = and .Contains and all other functions you are used to using.
An example of that is here:
datatable.AsEnumerable.Where(Function(row) CDate(row("Date")) = Now ).ToArray
Then, you can perform For each loop on that array of datarows. Or change .ToArray to .CopyToDataTable for a new table.
I hope this is clear.