In the interface, users can upload an Excel file, and then the data from the uploaded file will be displayed in a grid format.

OK. Easily done by creating a process with a second user input task where you can then display that data.

This is something that cannot be done within the same user interface.

Hello prashantk3550 

As Stefan mentioned you can use a second user input task after your upload file UIT and display the data. You don't have to save the information anywhere.

you can use the read excel functions and achieve this. Below is a link for the functions Plug-in which would be helpful to achieve your requirement. 

Excel tools
File to read

Hello Konduru,

In the first interface have a file upload component which would collect your file and save in a process variable which would be processed by a expression rule in a script task.

Below would be an example expression to read the excel file that you will call in the script task.

if(
  a!isNullOrEmpty(ri!document),
  {},
  a!localVariables(
    local!data: readexcelsheetpaging(ri!document, 0, a!pagingInfo(1, 5000)),
    local!onlyData: index(local!data, "data", null),
    local!employeeData: a!forEach(
      items: local!onlyData,
      expression: 'recordType!{b874b8c8-2b7c-4682-a353-db38d26b3d5d}RSS Employee Data'(
        'recordType!{b874b8c8-2b7c-4682-a353-db38d26b3d5d}RSS Employee Data.fields.{4d31204d-eee7-4358-a239-22528b0970b1}id': index(fv!item.values, 1, null),
        'recordType!{b874b8c8-2b7c-4682-a353-db38d26b3d5d}RSS Employee Data.fields.{e3826105-b66e-4f75-b773-ca82c5c47fde}name': index(fv!item.values, 2, null),
        'recordType!{b874b8c8-2b7c-4682-a353-db38d26b3d5d}RSS Employee Data.fields.{adf67688-eb07-43a8-9b74-432aada8fb3e}department': index(fv!item.values, 3, null),
        'recordType!{b874b8c8-2b7c-4682-a353-db38d26b3d5d}RSS Employee Data.fields.{6314bbfb-73fa-4250-aa5f-7c1bd371ebd2}city': index(fv!item.values, 4, null),
        'recordType!{b874b8c8-2b7c-4682-a353-db38d26b3d5d}RSS Employee Data.fields.{d0eca402-2b17-45d8-b350-3382cbfa7466}createdBy': "blahblah.blah@blah.com",
        'recordType!{b874b8c8-2b7c-4682-a353-db38d26b3d5d}RSS Employee Data.fields.{fb823c93-7630-49ba-b01c-7fd06a0da64a}createdOn': now()
      )
    ),
    local!employeeData
  )
)

Here the indexes would represent your excel columns and using these you can map your data while casting to your data type.

you can store it in the out put and in the next interface use this variable as an input and display

How much experience do you already have with Appian? If close to zero, I suggest to first complete the trainings in the Appian Academy, followed by the tutorials in the documentation.

Guiding you through all the steps necessary is a bit much for this place here.