Download the NVDA Remote Add-On
To install the add-on in a currently-running instance of NVDA, download it below, press enter on or double-click the file, and answer "Yes" three times when prompted by NVDA.
For NVDA 2019.3 and later
You can download the add-on that supports NVDA 2019.3 and later from here: Download version 2.5 for Modern NVDA
For NVDA 2019.2 and earlier
You can download the add-on that supports versions of NVDA older than 2019.3 from here: Download for earlier versions of NVDA