I think you're misunderstanding what the response contains.
Your initial code is good.
from requests import get
import json
url = "https://api.wheretheiss.at/v1/satellites/25544"
response = get(url)
You now have a response. see here for more info.
In this response you have status_code, content, encoding, and the response content as text. it also contains other information about the request. eg we don't want to continue if the request failed
You can simply parse the json by calling json.loads on the decoded response via response.text
parsed_json = json.loads(response.text)
or
parsed_json = response.json()
for item in json_:
print(item, json_[item])
I hope it helps. it is also duplicate to HTTP requests and JSON parsing in Python