Slider is not working for my website

First of all, thank you so much for such a fantastic theme that too free.
I followed the instructions that are there in the documentation and slider appeared once. Now it’s not coming only. Where I check view source there is HTML for slider generated.
I have modified header file a bit, However, it may not cause any problem. My website is

Thank you so much

Unfortunately, there is much more broken than just slider and I strongly recommend to reinstall the theme. There are missing several javascript files from footer and some of them are ones that comes with WordPress itself.

Probably you can try to track down where you made these mistakes but it will be much easier to start from scratch.

Yes you were absolutely right, many things were broken. As suggested, I tried from scratch and made my changes one by one. It works now.
Really appreciate your so quick response.
Thank you so much.