How to use value process variable in to Interface

Map a user input task with a similar type RI. Pass this PV in that RI in the forms tab of the UIT.

Yes, you can call the Process Model in the saveInto with the help of a!startProcess and pass the Process Model and Process Parameter which you have created in your PM as Process Variable.

I try, but it don't receive value form process model

I put this together to visually explain how data can be made to flow from a Process to a User Interface (and back again if required):

This should help you with the conceptual model of how it works, and give you an insight in where to look to solve your issue.

See, refer this below code and i have created one UI and created two rule inputs with the same name which i have created Process variable but make sure you have to make your Process Variable as "Parameter".

a!formLayout(
label: "Form",
contents: {
a!sectionLayout(
contents: {
a!sideBySideLayout(
items: {
a!sideBySideItem(
item: a!textField(
label: "Name",
labelPosition: "ABOVE",
value: ri!AS_Employee_Rahul_Task.name,
saveInto: ri!AS_Employee_Rahul_Task.name,
refreshAfter: "UNFOCUS",
required: true,
validations: {}
)
),
a!sideBySideItem(
item: a!textField(
label: "Email ID",
labelPosition: "ABOVE",
value: ri!AS_Employee_Rahul_Task.emailId,
saveInto: ri!AS_Employee_Rahul_Task.emailId,
refreshAfter: "UNFOCUS",
required: true,
validations: {}
)
)
}
)
}
),
a!sectionLayout(
contents: {
a!sideBySideLayout(
items: {
a!sideBySideItem(
item: a!textField(
label: "Contact Number",
labelPosition: "ABOVE",
value: ri!AS_Employee_Rahul_Task.contactNumber,
saveInto: ri!AS_Employee_Rahul_Task.contactNumber,
refreshAfter: "UNFOCUS",
required: false,
validations: {}
)
),
a!sideBySideItem(
item: a!fileUploadField(
label: "Resume Upload",
labelPosition: "ABOVE",
saveInto: {},
required: false,
validations: {}
)
)
}
)
}
)
},
buttons: a!buttonLayout(
primaryButtons: {
a!buttonWidget(
label: "Submit",
icon: "angle-double-right-bold",
/*value: ri!AS_Employee_Rahul_Task,*/
saveInto: a!startProcess(
processModel: cons!AS_Employee_Details_Rahul,
processParameters:{
Employee_Details:ri!AS_Employee_Rahul_Task,
cancel:ri!cancel
}
),
submit: true,
style: "PRIMARY"
)
},
secondaryButtons: {
a!buttonWidget(
label: "Cancel",
value: true,
saveInto: ri!cancel,
submit: true,
style: "NORMAL",
validate: false
)
}
)
)

I see so many solutions to so many challenges and still do not understand what the TO was asking for ?!? Is that only me?

So my question is: What do you want to achieve? In detail please!

I think this is a general question regarding how to get a process variable into an interface, via rule input..?

..which is general Appian functionality, my recommendation would be to start with some Tutorials.