How to display checkout even if cart is empty?

Question

WordPress

There is a mini cart, the floor of it should immediately be checkout (the cart is hidden if empty, if there is a product, then in the form of a widget), so I tried to load the checkout when adding a product via .load(), but there is an unpleasant delay, but on ios in general tin.
Couldn't do ajax a bit, because the site is already full of requests in the process.

In general, the question is how to make the checkout appear by default, and I will load it in the background with the hidden fields filled in.