It looks like you are using a different API than other people have mentioned, so the returned data format is different.
As such, you would need to use the appropriate path to an item you’re interested in. There’s a brief explanation on traversing JSON trees here.
Otherwise, I might recommend using something like the following to make it easier to find the appropriate path:
You can paste your JSON response in the left pane, then expand and select your desired item on the right and it will show you the appropriate path. Just replace the x in their path with $context.response.data.
Almost. There’s no top level property called “current” in the API response you’re using. It’s just weather → 0 → icon