Custom shopping cart icon/button

[ggtrobotics1]

Hello community,

I would like to know what actions is needed to make a custom shopping cart icon/button.

Things that I will like help in:
- Change how the icon/button looks
- Need to keep the number of items in my cart visible.  (The number that tells the customer how many items are in their personal cart.)
- Need to have the new cart and number of items in my cart stay inside my navigation bar.  The default shopping cart is always visible when scrolling up or down.  I do not want it to do that.  I want it to only stay inside my navigation bar.

I attached an example of what I'm looking to achieve.

Please provide me with the html/css code.

Sincerely,
Christian