I must gently suggest that you invest some time learning how FileMaker and relational databases work. Your description of your issues reveals a significant lack of understanding of how to use FileMaker.
I was able to navigate to apptwo using script and using global variable display the data from appone to apptwo but after new record addition the data is not getting cleared.
A "global" field is a field that will store the same data no matter what record is current. You can even delete all records from its table and a global field can still show the data entered into it. If you want to see different data in a global field, your script would need to be designed to update that field with different data.
But what you describe need not use any global fields. If the two layouts specify the same Tutorial: What are Table Occurrences? name in Layout Setup | Show Records From, you can simply place fields from the first layout on the second and the data you see on the first layout will show in these fields in the second layout. But this answer assumes things about the design of your database that may not be correct.
You can also link the table for the first layout to the table for the second layout and then the relationship can make it possible to show the data from the first layout one the second. A portal also relies on a correctly set up layout, but is normally used to display multiple records all linked to the current record on the layout where you placed your portal.
The two layouts depends on two tables. I have written my own scripts for the navigation to the new layout. Thanks for your immediate and prompt reply.