Creating a clothes/shoe website monitor/scraper that can integrate with discord webhooks

I need help with creating a website monitor application that works for Windows and can monitor any desired website that sells clothing and shoes such as [login to view URL] or Kith.com. I want it to monitor any newly added products and monitor any web pages for any changes (restocks). Once it detects a new product or restock, I would like it to connect with a Discord web hook and notify of the new product or restock via that web hook. Once the monitor detects a new product or change and it sends to the discord, I would also like it to have check-out links for each size. For example, if a shoe on Adidas (that is out of stock) restocks size 10 and size 10 only, then when it sends to the discord it will say all sizes out of stock except size 10 and then there is a link to go directly to the checkout page of that product. The sites that will mainly be used are [login to view URL], [login to view URL], and sites that use Shopify as their website provider. I would also like a keyword feature in order to filter out items that I do NOT want to be notified of. And, the program would need proxy integration to avoid bans by the website. I do not want this monitor to be a monitor that checks every 5 minutes or so (like some commercial website monitors do). If there is a product added, or restock, I want it to be detected instantly and sent to the discord instantly. I have included example pictures below of a monitor working in Slack. It is pretty identical to what I am looking for except in Discord.