To create a text as a link, click on the entry description field to open the text editor.

Add some text in the text editor and select the text you want as a link. Then click the Insert/edit link button from the editor toolbar.

In the insert/edit link modal URL field enter the link address.

Click the Save button to apply the changes.

Note: File upload is not supported. To create a link to a file (pdf, docx and other) upload your file to the external service like Google Drive, Dropbox or similar and copy the direct file link from their interface.