While Trying to integrate the libssh library with QT , getting key based authentication issue

Question

I need to make an application that runs in Raspberrypi where I can transfer files using ssh from the host Windows machine to the remote pi. and also execute a few read-a-file commands there. Hence I have to use these lines "#include <libssh/libssh.h>" the issue while I am trying to authenticate the sshsession using privatekey ,I am unable to do. Please find the respective function below:

ool SSHManager::connectWithPrivateKey(const QString &host, const QString &username, const QString &privateKeyPath) {
    if (!sshSession) {
        return false;
    }
    
    int verbosity = SSH_LOG_PROTOCOL;
    ssh_options_set(sshSession, SSH_OPTIONS_HOST, host.toUtf8().constData());
    ssh_options_set(sshSession, SSH_OPTIONS_USER, username.toUtf8().constData());
    ssh_options_set(sshSession, SSH_OPTIONS_LOG_VERBOSITY, &verbosity);
    
    if (ssh_connect(sshSession) != SSH_OK) {
        qDebug() << "Failed to connect to the SSH server";
        return false;
    }
    
    
    
    
    if (ssh_userauth_publickey_auto(sshSession,  nullptr, nullptr) != SSH_AUTH_SUCCESS) {
        qDebug() << "SSH public key authentication failed";
        
        
        if (ssh_userauth_privatekey_file(sshSession,  nullptr, privateKeyPath.toUtf8().constData(), nullptr) != SSH_AUTH_SUCCESS) {
            qDebug() << "SSH authentication with private key file failed";
            return false;
        }
    }
    return true;
    
}

I am unable to authenticate via password but not using my private key. the error what Iam getting in my QT is as below:

2023/09/08 20:39:29.411090, 2] ssh_client_connection_callback:  SSH server banner: SSH-2.0-OpenSSH_7.4p1 Raspbian-10+deb9u7
[2023/09/08 20:39:29.411586, 2] ssh_analyze_banner:  Analyzing banner: SSH-2.0-OpenSSH_7.4p1 Raspbian-10+deb9u7
[2023/09/08 20:39:29.411586, 2] ssh_analyze_banner:  We are talking to an OpenSSH server version: 7.4 (70400)
[2023/09/08 20:39:29.413103, 1] ssh_known_hosts_read_entries:  Failed to open the known_hosts file '/etc/ssh/ssh_known_hosts': No such file or directory
[2023/09/08 20:39:29.415063, 2] ssh_kex_select_methods:  Negotiated curve25519-sha256,ssh-ed25519,chacha20-poly1305@openssh.com,chacha20-poly1305@openssh.com,aead-poly1305,aead-poly1305,none,none,,
[2023/09/08 20:39:29.574564, 2] ssh_init_rekey_state:  Set rekey after 134217728 blocks
[2023/09/08 20:39:29.574564, 2] ssh_init_rekey_state:  Set rekey after 134217728 blocks
[2023/09/08 20:39:29.574564, 2] ssh_packet_client_curve25519_reply:  SSH_MSG_NEWKEYS sent
[2023/09/08 20:39:29.574564, 2] ssh_packet_newkeys:  Received SSH_MSG_NEWKEYS
[2023/09/08 20:39:29.577011, 2] ssh_packet_newkeys:  Signature verified and valid
[2023/09/08 20:39:29.577968, 1] ssh_pki_import_pubkey_file:  Error opening C:\Users\****/.ssh/id_ed25519.pub: No such file or directory
[2023/09/08 20:39:29.578465, 1] ssh_pki_import_privkey_file:  Error opening C:\Users\****/.ssh/id_ed25519: No such file or directory
[2023/09/08 20:39:29.579460, 1] ssh_pki_import_pubkey_file:  Error opening C:\Users\****/.ssh/id_ecdsa.pub: No such file or directory
[2023/09/08 20:39:29.579955, 1] ssh_pki_import_privkey_file:  Error opening C:\Users\***/.ssh/id_ecdsa: No such file or directory
SSH public key authentication failed
[2023/09/08 20:39:29.581333, 1] ssh_userauth_try_publickey:  The key algorithm 'ssh-rsa' is not allowed to be used by PUBLICKEY_ACCEPTED_TYPES configuration option
[2023/09/08 20:39:29.581333, 2] ssh_userauth_publickey_auto:  Tried every public key, none matched
[2023/09/08 20:39:29.581942, 1] ssh_pki_import_pubkey_file:  Error opening new_key.pub: No such file or directory
[2023/09/08 20:39:29.581942, 1] ssh_userauth_privatekey_file:  Public key file new_key.pub not found. Trying to generate it.
[2023/09/08 20:39:29.582439, 2] ssh_pki_import_privkey_base64:  Trying to decode privkey passphrase=false
[2023/09/08 20:39:29.585288, 1] ssh_userauth_publickey:  The key algorithm 'ssh-rsa' is not allowed to be used by PUBLICKEY_ACCEPTED_TYPES configuration option
SSH authentication with private key file failed

Kindly note that I am using private key in Openssh format. Please help me to find a solution to authenticate the remote raspberry pi using privatekey libssh method.