How to set up chirpstack with RAK2243 and Raspberry pi?

hi Velav,
I did the above set up (by using os image and etcher). And I configured the chirpstack with default lora server IP address 127.0.0.1. Can I change that IP address? Where did I get IP address?
I found this RAK free cloud LoRaServer for testing!
But I can’t open this link https://www.rakwireless.com/en/download/LoRa/LoRa-Server-Cloud