how can i add to the GetSaveFileName() windows dialog box checkboxes, selects, labels, ..., without using mfc or any 3rd party library thanks in advance caesar

The flags member of the OPENFILENAME structure must have the OFN_ENABLETEMPLATE bit set. Then the lpTemplateName member contains the dialog resource to use.

ok, how do i use the template name and what should i do afterwards

From MSDN:

To define additional controls for an Explorer-style Open or Save As dialog box, use the OPENFILENAME structure to specify a template for a child dialog box that contains the additional controls. If your child dialog template is a resource in an application or dynamic-link library, set the OFN_ENABLETEMPLATE flag in the Flags member and use the hInstance and lpTemplateName members of the structure to identify the module and resource name. If the template is already in memory, set the OFN_ENABLETEMPLATEHANDLE flag and use the hInstance member to identify the memory object that contains the template. When providing a child dialog template for an Explorer-style dialog box, you must also set the OFN_EXPLORER flag; otherwise, the system assumes you are providing a replacement template for an old-style dialog box. Typically, if you provide additional controls, you must also provide an Explorer-style hook procedure to process messages for the new controls.

You can create your child dialog box template as you do any other template, except that you must specify the WS_CHILD and WS_CLIPSIBLINGS styles and should specify the DS_3DLOOK and DS_CONTROL styles. The system requires the WS_CHILD style because your template defines a child dialog of the default Open or Save As dialog box. The WS_CLIPSIBLINGS style ensures that the child dialog box does not paint over any of the controls in the default dialog box. The DS_3DLOOK style makes sure that the appearance of the controls in the child dialog box is consistent with the controls in the default dialog box. The DS_CONTROL style makes sure that the user can use the TAB and other navigation keys to move between all controls, default or custom, in the customized dialog box.