If each of the 7 files has the same data structure (i.e. broken down based on 'records') then it will be easy to bring each file in individually in the Paxata library and then append the 7 datasets into a project to create a single dataset. Let me know if this helps.
This depends on whether the files are local on your system or if your data is on a cloud based data storage system like an Amazon S3 or Azure.
If the files are local on your system, then you must first import these 7 files on to the library as 7 separate datasets. After loading these files into the library, open a Paxata project with one of the datasets as your base dataset and then use 6 append steps to union these files together.
Alternatively, if your files are located on S3, Azure or any Paxata supported cloud data storage system. You can use a wildcard pattern to glob these datasets together before bringing it into the library.