i didn`t understand where to ask forgive if i am wrong. can we merge two databases if yes how ?

No.

Depends on your definition of "merge". What are you hoping to achieve by having one file?

You could, for example, have add table occurences from one file to another so you have access to the second file.

There is a process for actually combing to files. Off the top of my head, I can't remember the exact order, but it's something like:

Import custom functions

Import tables

Create table occurrences & relationships

Create blank layouts

Import scripts

Copy layout elements