Real-time product updates for dropshipping

Dropshipper has a widget for the website. Customer selects group of products widget. Dropshipper sends info via API to my shop - the image, product name, description, my cost, etc. I add on my sales information - different markups, different minimum, etc. Need to display those products with calculated pricing on the store. Customer makes selection and buys. That info is sent back to dropshipper for shipping to the customer

The issue: Do I need to download their entire product database? There are too many products and inventory changes all the time, so I can’t download their entire database every 2 minutes for latest update. They already have it on their system of what is in stock. I just need to download and display the 10 or 20 products that the dropshipper send me. Products can be dropped, new ones added, out of inventory - the list goes on and on.

Example: Customer puts “Red” “Sweater” “Medium” into the widget, and the dropshipper sends 15 different choices available at this moment to the shopify store. I need to add those into the store, but can’t have products in the store that no longer exist, new products that are added, out of inventory, etc. The dropshipper’s widget sends me this info on what is available in real-time.

I can’t just put all the products on the store all the time available. I can’t manually add and drop products every 2 minutes.

Is this the way it can work? If not, any suggests on how to accomplish it?