Files of different layouts can be appended together using Paxata. There are two important things that you should understand during this append process. The final appended dataset will contain every column present across all the data files (No duplicates). Secondly, the column values would display blank for the files that do not have that specific column.
Take the example of two datasets as shown in the image below:
Dataset 1:

Dataset 2:

The final appended dataset will look like this: