I believe that there is a plugin on Woothemes which does this called “Storefront Checkout Customiser” which has a distraction free checkout feature.
https://www.woothemes.com/products/storefront-checkout-customiser/
Otherwise you can probably add something in functions.php or in styles.css to remove the header and footer. For CSS you’d target the body class (which contains the page id) and then element of header/footer.
For example in CSS (Don’t use this code as it won’t work on your site. It’s for Storefront Demo):
.page.page-id-6.page-template.page-template-template-fullwidth.page-template-template-fullwidth-php.custom-background.woocommerce-checkout.woocommerce-page.right-sidebar.woocommerce-active.sbc-meta-inline-bottom.sd-buttons-rounded.sd-buttons-flat.sd-header-compact.sd-typography-helvetica.storefront-pricing-tables-active.storefront-product-hero-active.swc-shop-alignment-center #masthead {
display: none;
}