Importing CSV files to append to table data

I watched the tutorial on this, but still a little fuzzy. On a form can I make it so that a data entry user can import a cvs with only a few button clicks? choose the columns they need and have it append a table or does it have to make a new table?

@mlefler can you be more specific about what you're trying to do here? You can upload a CSV using a filepicker component, and then pick our which columns you want to use via Javascript.