Checkout provides you parameters to checkout directly without clicking single product page's "Add To Cart" button.
1) The parameter to add the product for checkout
?aero-add-to-checkout=<product_ID>&aero-qty=<count>
2) Sample URL
Here is Sample URL
https://www.yourdomainhere.com/checkouts/YourAeroCheckoutPageName/?aero-add-to-checkout=87&aero-qty=6
3) Where to get parameter
For example, here 87 is your product id in WooCommerce. You can find it by going to your product list and checking the below shown place.
4) Behavior in case of variations/variable
Similarly, If you want to add a particular variation of a variable product, you can directly put the Variation ID.
Find the variation ID by edit the product and checking the below shown place.
This will add the product with pre-selected variation Blue color & XXL size for checkout
Here is Sample URL
https://www.yourdomainhere.com/checkouts/YourAeroCheckoutPageName/?aero-add-to-checkout=2532&aero-qty=6
Final Output:
