I'm trying to deploy the azure template located here https://azure.microsoft.com/en-us/resources/templates/sharepoint-three-vm/
Everything appears to be working fine accept the first three variables shown in the screen shot. screenshot
Can someone help shed some light on the problem?
Cheers
Your error message says it all.
Replace the image size, or replace the region you're trying to run your PowerShell at.
Edit: instead of trying to guess your way into finding the right VM size and the appropriate location to host it, take a look at the Azure Products by Region page. All the VM sizes are there with their available locations.