Create a fast checkout bot for Kickz to buy limited sneakers

I need an auto-checkout bot, that will automatically checkout a pair of shoes. Once on the page of the shoes I want the bot to have all the information pre loaded so that it can select the size of shoe add to cart and complete the entire checkout process with credit card info and shipping and billing address. I want a bot for kickz and maybe if its possible also for footlocker. It should run in the backend, so if the site or browser crashes, the bot should have still the ability to checkout faster than others, so it should be very fast and checkout succesfully. Im not sure what time this will take to build a bot like this but I want it to be lightning fast to beat the existing bots that are out there. So please bit your most reasonable price even if it is outside the budget