How to post a long message using standalone?

Question

In contact with

string site = "https://api.vk.com/";
            string param1 = $"method/wall.post?owner_id={_myOwnerId}&message={param}&access_token={_accessToken}";

Similarly, I try to publish a long text in my group. I get a response from the server "414 Request-URI Too Long".
How else can I post a long text?
Why do I send the same text through the form https://vk.com/dev/wall.post and it is published by sending the text through the above link and the server gives an error?

Answer 1

And you try not to send a get request, but shove the post and your text into the body