function allow_custom_font_uploads($mimes) {
    $mimes['woff'] = 'font/woff';
    $mimes['woff2'] = 'font/woff2';
    return $mimes;
}
add_filter('upload_mimes', 'allow_custom_font_uploads');
 
ADD THIS IN FUNCTION.PHP

THEN DOWNLOAD PLUGIN : WP Add Mime Types

THEN ADD : woff = font/woff
woff2 = font/woff2