You can log your browser's traffic to see the actual GET or POST requests. Use Fiddler or something like that. And then you'll be able to reuse them with http client.
is it possible, but I would say it is extremely difficult, each site will have a unique set of parameters you will need to manually fill, youtube I would guess is very complex
For those who needs this later, you can set up http proxy and send a simple get request to https://api.ipify.org , it will give you the ip adress in plain text, no need to parse the json.
One of many simple and easy ways to do it.
