How to save Any type variables value in process model?

Any type Inputs will not create the node inputs automatically since it dont knows the type, but you can create a new input using "Add new input"

Any type Inputs will not create the node inputs automatically since it dont knows the type, but you can create a new input using "Add new input"

But how can I get the value of Any type variable in this newly created variable?

Save the node input into a process variable. Since we are mapping this new node input(AC) with Interface input, we will get the value entered in the form to ac first(Node input) and then to pv variable.

You must create node inputs (activity class parameters) and save the node inputs into process variables if you want to use their values elsewhere in the process

https://docs.appian.com/suite/help/18.1/Data_Tab.html

Hope helps

Basically you can't. Generally speaking, you should be saving into PV of the correct type upon form submission. What's the use case where you would want to use 'Any Type'?