Customizing Menu & Header image

Hi,

I have created one website using wordpress package which is located here
https://www.welancers.com/pj/

I want to customize its Top menu & add some custom links of some other location. Right now I have added one pluging which redirects to the specific url when click on that page link. But is there any better way to achieve this?

Also I have integrated OSTicket System in my website on wordpress, which is located in the sub folder as
https://www.welancers.com/pj/helpdesk

The integration is easy as just needed to include my theme’s header & footer files into osticket’s template file.

There is just one issue with this, I want to add customer header image for osticket package but as my theme’s header file is included there, I am not able to change the header image for “helpdesk” folder files only.

I have installed a plugin for setting different header images for different pages but it is not working on “helpdesk” folder files.

So what I want to know is,
1) is there any better way to give custom links in the top menu
2) how can we add custom header images for every page as well as on the “helpdesk” sub folder files.

Please give you suggestions,
Thanks in advance.