How to solve Normal Captcha using 2captcha in C# language?


Hello anyone please can help me solving normal captcha using 2captcha in c# language , in their website they say you can use submit the captcha manually using Multipart sample form this is it:
<form method="post" action="" enctype="multipart/form-data">
    <input type="hidden" name="method" value="post">
    Your key:
    <input type="text" name="key" value="YOUR_APIKEY">
    The CAPTCHA file:
    <input type="file" name="file">
    <input type="submit" value="Upload and get the ID">
-If everything is fine server will return the ID of your captcha: OK|2122988149
-After 5 seconds send GET request to get the result: GET
-If captcha is already solved server will respond with the answer token: OK|W9H5K
-If captcha is not solved yet server will return CAPCHA_NOT_READY result. Repeat your request in 5 seconds. If something went wrong server will return an error code.
anyone can help me please?