Hello,
2) Add the below code to Theme Options > Custom CSS
.single-product .et-footers-wrapper {
margin-bottom: 70px;
}
4) Sticky header means that the header displays over the page content always when you scroll down (Fixed type) or only if you scroll down and then to the top (Smart type). If you don’t want to have that overlay of the header you can only disable the Sticky header option.
Regards