"Back to top" icon – can I move to other side

1. How do I move the “back to the top” icon over to the left side with the rest of the navigation icons?

2. And is there any way to change the color of it?

3. Is there a way to make the tiny scrolling navigation button for the mobile menu larger?

4. And can I change the color of the text and background that pops up when hovering over it?

Thank you!