DropBox Https Api Request : What should I do?

I dont know how dropbox works, if they only upload changes to files or they upload the full file everytime (i imagine the first one) but you need a php script on your server (app?) to handle the upload of files, here is a small example of a zip upload (I have edited it because it is code from an old project with extra stuff you dont need so maybe I deleted something but is pretty much this)

         WWWForm formData = new WWWForm ();
 
         byte[] formBytes;
 
         formData.AddField("action", "zipupload");
 
         if (File.Exists("path/to/the/files/example.zip")) //HERE YOU FIND THE FILE TO UPLOAD
         {
             formBytes = File.ReadAllBytes("path/to/the/files/example.zip");
             formData.AddBinaryData("form", formBytes, "Form.zip");
         }
 
         string url = "http://URLtoYourSite/upload.php"; //CHANGE TO YOUR URL
 
         using (UnityWebRequest www = UnityWebRequest.Post (url, formData)) {
 
             string authorization = Authenticate (stUsername, stPassword); //only use this if you need user password
             byte[] boundary = UnityWebRequest.GenerateBoundary ();
 
             www.SetRequestHeader ("Authorization", authorization);
 
             yield return www.SendWebRequest ();
 
             if (www.isNetworkError || www.isHttpError) {
                 Debug.LogError (www.error);
             } else {
                 Debug.Log ("Files uploaded.");
                 StringBuilder sb = new StringBuilder ();
                 foreach (KeyValuePair<string, string> dict in www.GetResponseHeaders ()) {
                     sb.Append (dict.Key).Append (": \t[").Append (dict.Value).Append ("]\n");
                 }
 
                 Debug.Log ("Response headers: " + sb.ToString ());
                 Debug.Log ("Response text: " + www.downloadHandler.text);
             }
         }

`then you need the php to move the files to your location in your server

AFTER ABOUT 20HR OF STUDY I've managed to have a working Script...Really I fell like I was under torture :-). This script maybe is not "Super Clean" (I've a lot of missing info about true coding). It took the "API URL", pass BODY PARAMETERS, pass Authorization Token. I was unable to use the WebRequest.Post because of Json Decode Warning. In the way below insted it work! Thank you for Help @xxmariofer. (Now I'm stucked in JsonDeSerialize but maybe i will use some dirty String Search, only need to find Shared_Link in Response)

 public string Url = "https://api.dropboxapi.com/2/sharing/create_shared_link_with_settings";
         public string Token = "MySuperSecretToken";
         public string Path = "/Shared Folder";
 
 // STRUCT DEI PARAMETRI DEL BODY
         public struct MyStruct
         {
             public string path;            
         }    
         // GENERO STRUCT
         public MyStruct DataFormBody;
 
 IEnumerator Post_Easy()
             {
                 // Assegno la Path
                 DataFormBody.path = Path;
                 // Converto in JSon
                 string JSonBody = JsonUtility.ToJson(DataFormBody);
                 // Passo il Parametro POST a UnityWebRequest
                 var request = new UnityWebRequest(Url, "POST");
                 // Codifico il Json in Byte Utf8
                 byte[] bodyRaw = System.Text.Encoding.UTF8.GetBytes(JSonBody);
                 // Assegno il Body in Parametro Upload
                 request.uploadHandler = (UploadHandler) new UploadHandlerRaw(bodyRaw);
                 // Assegno il Download del Response
                 request.downloadHandler = (DownloadHandler) new DownloadHandlerBuffer();
                 // Imposto l'Header di Autorizzazione
                 request.SetRequestHeader ("Authorization", "Bearer " + Token);
                 // Imposto la tipologia di comunicazione
                 request.SetRequestHeader ("Content-Type", "application/json");
                 // Invio la richiesta alla API DropBox
                 yield return request.Send();
                 
                 // Verifica se ci sono errori di connesione
                  if (request.isNetworkError || request.isHttpError)
                  {
                      // Riporta l'errore di connesione
                      Debug.Log(request.error);
                      // Riporta ulteriori informazioni riguardo l'errore
                      string message = request.downloadHandler.text;
                      Debug.Log("response: " + message);                     
                  }
                  else
                  {
                     // Scarica la risposta
                     string message = request.downloadHandler.text;
                     // Debug Status Code
                     Debug.Log("Status Code: " + request.responseCode);
                     // Debug Risposta
                     Debug.Log("response: " + message);
                     // Scrivo la risposta in un file
                     File.WriteAllText("DropBox Response.txt",message);                    
                  }                
             }