use the start wizard

use File/Open menu 

the File menu offers a list of the Most Recently Used workspaces

use the toolbar

drag the icon representing a text over TeXT Handler's window or icon 

import contents from the clipboard

drag and drop a text selection from Word or Wordpad or other word-processor that supports the operation

split  ( spawn ) a document into its component paragraphs and choose a different activity for each.

Refer to built-in help in TeXT Handler.