How to extract particular column's from a table?

There are two ways of doing this into powerbi.

1. In the Query Editor, Select particular column, Right Click and Remove other columns.

2. Connect your model to DAX Studio and Write the below syntax.

EVALUATE

               TABLE[COLUMN NAME]

Run this Query againest your model and you can extract the results into .TXT file. 

3. In the Query editor, You can select the particular column in your table and convert it to the list.