Before testing your appplication, make sure you have completed the following requirements:
Test your Live App in Ledger Live
In the Ledger Live developer tab, enable the option Enable Platform dev tools. It will allow you to use a browser-like developer tools window to inspect your application.
Then click on Browse next to Add a local app and import your application’s Manifest file.
Your application appears in a new row below.
Click Open to open your application inside Ledger Live.
You are now able to locally and autonomously test your application integration inside Ledger Live.
You can refer to the Tutorial for more details.