No, you cant change lan ip via the local management, nor do you need to.
Give the quick start guide another read through. Here are the steps summarized.
1. If you need to change wan settings before the MX can get internet access, connect your laptop to LAN port.
2. Sign in and modify wan uplinks as needed.
3. Flipp back to the status page and check if the box can reach the internet.
4. Hopp on to dashboard.meraki.com, create your network and modify settings. For example changing the vlans and ip subnets.
5. Add your mx67w to the network you just created.
If the MX can reach the internet you will soon see that the device is green and online under the sd-wan an security appliance status page.
MLL