How I can send mouse click in powershell?

If you don't feel like writing your own function, the Windows Automation Snapin for Powershell has a Send-Click() function. Alternatively you can import some functionality from the Windows API using mouse_event() although I would recommend SendInput() as it supersedes mouse_event(). Below is a fully functional sample that uses P/Invoke to get the functionality you want and send a left click to a specified screen coordinate:

$cSource = @'
using System;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Windows.Forms;

public class Clicker
{
    // https://learn.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-input
    [StructLayout(LayoutKind.Sequential)]
    struct INPUT
    { 
        public int        type; // 0 = INPUT_MOUSE
                                // 1 = INPUT_KEYBOARD
                                // 2 = INPUT_HARDWARE
        public MOUSEINPUT mi;
    }

    // https://learn.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-mouseinput
    [StructLayout(LayoutKind.Sequential)]
    struct MOUSEINPUT
    {
        public int    dx;
        public int    dy;
        public int    mouseData;
        public int    dwFlags;
        public int    time;
        public IntPtr dwExtraInfo;
    }

    // This covers most use cases although complex mice may have additional buttons.
    // There are additional constants you can use for those cases, see the MSDN page.
    const int MOUSEEVENTF_MOVE       = 0x0001;
    const int MOUSEEVENTF_LEFTDOWN   = 0x0002;
    const int MOUSEEVENTF_LEFTUP     = 0x0004;
    const int MOUSEEVENTF_RIGHTDOWN  = 0x0008;
    const int MOUSEEVENTF_RIGHTUP    = 0x0010;
    const int MOUSEEVENTF_MIDDLEDOWN = 0x0020;
    const int MOUSEEVENTF_MIDDLEUP   = 0x0040;
    const int MOUSEEVENTF_WHEEL      = 0x0080;
    const int MOUSEEVENTF_XDOWN      = 0x0100;
    const int MOUSEEVENTF_XUP        = 0x0200;
    const int MOUSEEVENTF_ABSOLUTE   = 0x8000;

    const int screen_length = 0x10000;

    // https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-sendinput
    [System.Runtime.InteropServices.DllImport("user32.dll")]
    extern static uint SendInput(uint nInputs, INPUT[] pInputs, int cbSize);

    public static void LeftClickAtPoint(int x, int y)
    {
        // Move the mouse
        INPUT[] input = new INPUT[3];

        input[0].mi.dx = x * (65535 / System.Windows.Forms.Screen.PrimaryScreen.Bounds.Width);
        input[0].mi.dy = y * (65535 / System.Windows.Forms.Screen.PrimaryScreen.Bounds.Height);
        input[0].mi.dwFlags = MOUSEEVENTF_MOVE | MOUSEEVENTF_ABSOLUTE;

        // Left mouse button down
        input[1].mi.dwFlags = MOUSEEVENTF_LEFTDOWN;

        // Left mouse button up
        input[2].mi.dwFlags = MOUSEEVENTF_LEFTUP;

        SendInput(3, input, Marshal.SizeOf(input[0]));
    }
}
'@

Add-Type -TypeDefinition $cSource -ReferencedAssemblies System.Windows.Forms,System.Drawing

# Send a click at a specified point
[Clicker]::LeftClickAtPoint(600, 600)