how do i use the rest api to print the json result in a third party website
The rest api is well documented in
https://docs.loraserver.io/lora-app-server/integrate/rest/
https://YOUR_SERVER/api
You will need a JWT token: https://jwt.io/ <- Very usefull site
As well as define your JWT_SECRET in the lora_app_server. If you are in testing fase I recommend you to use an easy secret.