To insert text files:
The file browser appears. The Files area of this window shows all files and directories that are contained in the directory whose full pathname is shown in the Selection field.
In the Filter window that appears, enter a string and wildcard character (for example, *.txt), then click the Apply or OK button. Only those files that fit your match criteria appear in the Files area.
You can preserve the line breaks, in which case each line will appear as a separate paragraph, or you can merge the lines and form paragraphs. You can also choose to convert the text file into a table. See Converting Text Files Into Tables.