How to create open and create master module entry from another master

I have some master module. Some master module entry have reference with another master module. I want to create new entry from another form. On specific key down event.  Example:-

Product Module where i can create edit and delete product. In that entry module there is one field Product Unit which also has specific module. I want to go to and create new unit when i Press ctrl + N in Product Unit textbox. and return back with that value to continue product create or edit.

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