If you need more flexibility for adding new columns than the ones provided out of the box in Power Query, you can create your own custom column using the Power Query M formula language. Imagine that ...
When working with address data, you may encounter situations where you need to merge multiple columns, such as address, town, and postcode, into a single column. Power Query makes this task a breeze.
Fill Up the Null Values Fill Up and Down:: Land the power query >> Suppose you have null Values Down >> Right click on the column >> We have Option Filll >> If you want to fill you can click on Down ...