Having one request object as a Method Signature parameter, which constitute all the required parameters

Question

A method signature is part of the method declaration. It is the combination of the method name and the parameter list.

So instead of specifying a list of parameters

Answer 1

Some answers to the question Building big, immutable objects without using constructors having long parameter lists are probably relevant here also (it doesn't really matter if you're dealing with methods or constructors, a constructor is just a special method, after all).