cart icon floating right on sticky menu so when scroll down can see cart

Good morning
it's default of theme. You can check on my demo: https://kuteshop.kutethemes.net/, it's the same. In this case, you need to custom by yourself or connect to Customized Services, where they will help you. I am really sorry because i do not support for custom work.
If you have other questions, do not hesitate to contact with me
Regards