filter in datatable

Hello
I have a one datatable,that contains many field like datatype,display_name etc.
datatype_contains bit,varchar,decimal etc.now i want replace bit to 'Boolean' and varchar to 'String'.
how this is possible.if any one have any idea let me know as earlier as possible.
please see the below image.


Thanks In Advance.
Any Help will be Appriciated.
Khushboo Nayak.

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