Hi everyone! I'm trying to make a bot for Tumblr or Twitter, but both require OAuth requests. I'm not sure how to use a Net.WebRquest this way. I've searched all over and found very scarce information. I believe I am supposed to add some credentials in the header. This is what I have tried:

Code:
Dim request As WebRequest = WebRequest.Create(URL)
request.Headers.Add(HttpRequestHeader.Authorization,
  $"OAuth realm=""https://api.tumblr.com/"",
  oauth_consumer_key=""{APIKEY}"",
  oauth_token=""{TOKEN}"",
  oauth_signature_method=""HMAC-SHA1"",
  oauth_signature=""?"",
  oauth_timestamp=""{(Now - New DateTime(1970, 1, 1)).TotalSeconds}"",
  oauth_nonce=""{Now.GetHashCode()}"",
  oauth_version=""1.0""")
Assuming APIKEY and TOKEN are valid, I am still getting Error 401: Unauthorized. Also, what do I put in "oauth_signature"? That did not make any sense to me. This website contained the most useful information: https://oauth.net/core/1.0a/

Has anyone else here dealt with OAuth requests before, that can help me? If there were any examples out there, that would be wonderful. Thank you so much in advance.
~Nic