How it was possible - this type of Signature in pdf form.

[#1]

see this bellow link,

go to signature field.

when i type my name in text box

the signature turning in to hand written signature.

how it is possible in acrobat? or what other ways to do like this?

http://opendoormultiservices.com/w9

[#2]

Looks like eSign (formerly EchoSign).

eSign service, e-signatures online, formerly EchoSign | Adobe Document Cloud